MarSubstSel

FAQs about Marine Substrate Selection 1

using Reptilite in a reef tank? 1/5/12
How's it going?
<Fine thanks>
I am in the process of moving to a new house just a few miles away, but still the thought of moving my 125g reef tank gives me headaches. I have come to the conclusion that keeping the sand is a big no no. I still don't know exactly why it is a bad thing, so if you could explain that would be helpful. But my main my question, have you heard anything of a product called Reptilite?
(http://www.reptilesupply.com/product.php?products_id=1024 )
<Mmm, yes. Am friends w/ some of the fellows that run the marketing end of CaribSea>
As you can see it is made by CaribSea, and it seems to have the same qualities of reef sand. It also says "This low impact substrate also contains strontium and magnesium; while being free of silica and phosphates," which almost looks like it should be on the front of a bag of reef sand. I also remember seeing my LFS use this for their tanks. If all is okay, are there any issues with having the very fine grain size that this one has?
<Not much. Please read here re: http://www.wetwebmedia.com/marsubstsel.htm
and the linked files above. Bob Fenner>
Jeremy

New 1000 gallon set up: substrate question and how to move 3 year ... subst. sel., DSBs 1/2/12
old fish to it
Hello to all and Happy New Year! I work out of my house and I am on your website everyday. My knowledge has now exceeded the LFS I am afraid and I am tired of making the wrong decisions based off their bad advice. I have no "fish buddies" -- just you guys -- and I consider you my "fish buddies" and take your advice. My addiction to the hobby has grown in the past three years since I started out with a 120 in my upstairs office.
I have built out my basement recently ( will refer to it later in the email as "downstairs") around some showcase tanks that are built into a wall with catwalk access behind the wall.
Before I pull the trigger on buying 2400 lbs of sand for the substrate for these new tanks -- just want to double check with Bob Fenner or the crew ( it is my dream to some day meet Bob)
<Come out to MACNA in TX this year>
on this large sand purchase -- as it will be expensive and the LFS does not recommend buying this much sand ( first time they are saying buy less not more).
<Not necessary... if you have other means of providing biomineral and alkalinity... and your livestock doesn't require such>
The new set up downstairs is (1) 265 gallon tank and (3) 150 gallon tanks going back to a remote 300 gallon sump. I have the water and salt in the tanks and it is all plumbed and running. The question is how much sand to use as substrate to do it right to help with nitrate reduction and not create a bad situation from use of sand at less than 4" as I read on WWM.
<Mmm, yes... though a DSB could be just part of all the tied in volume
here>
LFS recommends like 80 lbs sand for (1) 150 tank for example. I think this would be less than 1" of sand.
<Yes>
I have other tanks upstairs right now in operation for 3 years that will eventually be torn down and the inhabitants and live rock brought downstairs. I measured the sand off at like 2" in those tanks that the LFS set up. I have always had high nitrate in these tanks. The LFS wants me to mimic the sand depth like I have upstairs for the new downstairs tanks -- so basically like 1 to 2" deep ( aesthetic) downstairs.
<So?>
I am afraid that this aesthetic depth -- which I do like the looks of -- will cause problems with toxic water situations from what I read?
<Yes; your high nitrate situation/s will continue>
So I am trying to figure out if I am over thinking this -- or if I have to have 4" to be safe of sand depth -- or if 1" - 2" would be OK to use....I am not real excited about the depth of 4" of sand. I don't like the aesthetics of it or the cost -- but want to use sand for sure as a substrate and want to use more than 1/2" of sand in the tanks
<Mmm, place this depth, or greater, in even just part of your 300 gal. sump>
From what I gather -- to do a DSB right would mean minimum of 4" of sand depth in all tanks.
<Mmm, no; not necessarily. The others could have a shallow depth>
The tanks are all 31" high -- so that would take some of my usable swim height away -- beside the aesthetics and cost that I don't like.
I figure to need about 2400 lbs which would be about (60) 40 lb bags to achieve 4" in all tanks and also to have a 4" to 6" DSB in the sump refugium chamber.
<Just try the latter>
I am going to use Carib sea Fiji pink reef sand with granule size per Carib sea site between .5 mm to 1.5 mm. This thus gets me some granules of sugar fine grade and some of medium grade per Anthony Calfo's grade system on WWM. I was going to mix the Fiji pink with Carib sea sea flor special grade reef sand to get some bigger pieces (Carib sea website says 1.0 mm to 2.0 mm granule size for special grade sand) but decided that mixing the two types was not indicated per WWM and that special grade granule size would be too big for DSB to work right?
<For optimal function, yes>
I elected not to go with the sugar fine Carib sea as my LFS does not have it to start with -- and this is too big a set up to have the 2 year half life of that particular sand from what I read that it will dissolve to half -- and to have to add 50% more volume in 2 years was something I did not want to pay for / have to do.
So -- do I need 4" if I am going to use sand and don't want to use just 1/2"? Thank You!

In the refuge chamber - -is sand good enough --- or do I need to use mineral mud too?
<You don't have to>
There will be a big skimmer in another chamber in the sump.....Also live rock in the sump besides all the tanks will also have live rock. The tanks will all be reef tanks in this set up downstairs I forgot to mention.... The LFS sent me home with 3 gallons of mineral mud for the refuge chamber and told me to mix it in with the sand. I did not to it -- I just used sand....This OK?
<Yes; though the mineral mud won't hurt anything>
Not sure what type of macroalgae I will use yet -- need to research that still.
<Good. Read here: http://www.wetwebmedia.com/refugalgfaq2.htm
Lastly: I have read about all the QT methods on the WWM site. I have never personally had a fish tolerate a FW dip -- so I don't try it anymore - they get too stressed...Everything that the LFS sells is parasite ridden.
My water from the tanks that have been in operation for 3 years upstairs undoubtedly has some level of Ich or other parasites in it -- as the fish have all had Ich at some time or another -- either when they were added or when a new fish was added -- and iched everyone out. These fish are all 3 years old and they are beautiful specimens --- there are like 20 of them.
They exhibit no signs of parasites now -- but likely they could be carriers.
<Likely; but with immunity of sorts>
Before I take these fish out and bring them downstairs to their new tanks -- do I need to QT them or put them in a medicine tank?
<No>
I have both types of these tanks running now -- a 110 Qt tank and a 55 medicine tank that has had copper in it. I just feel that moving these fish twice -- i.e.. from upstairs to QT then to new displays could kill them from stress.
If I move them straight to the new tanks -- I would guess I would then have Ich in that new system water?
>So?<
Then -- even if I QT / medicate all new fish coming in after them -- and they come in healthy to the new display tanks -- once they hit the new tank display water -- they could Ich out -- as there would be Ich of some form in there from my 3 year old fish introduction?

It would take a very long time to get all 20 fish through QT and into the new downstairs display tanks -- as currently they reside in 3 separate tanks upstairs and all could not go through QT together at same time -- and these 3 year old fish and these old tanks need to exit the room they are in upstairs and get into the new tanks downstairs ASAP -- as this room they are in upstairs needs to be turned into a bedroom -- and these tanks they are in upstairs will be sold back to the LFS soon after
In reality -- what is the likelihood that a piece of Liverock or a coral or a fish in the future that went through QT and all the best practices would not end up with one parasite on them anyway == somehow that slipped through -- and would inflict the main display anyway?

 Then I went through all the work of QT the (20) 3 year old fish for no reason and maybe even would loose <lose> some of them from all the stress?
I don't know = I want to do it right.....
Thanks!
David
<All a matter of degree... like most all the universe. Congratulations on your new basement systems. Bob Fenner>
Re: New 1000 gallon set up: substrate question and how to move 3 year old fish to it 1/2/12
Hi Bob -- I am so excited to have had you answer my questions and hope you are having a good new years day. Just a couple follow up points /
questions and then I will let you enjoy your evening.
1) sounds like having a 6" DSB in the remote 300 gallon sump (will be about 400 lbs of Fiji Pink to achieve this depth in the refuge chamber) will be sufficient to achieve some Natural Nitrate reduction. If I employ the 4" depth in all display tanks too -- will that benefit me a whole lot more for nitrate reduction than just doing it in the sump == or not to a great degree that it is worth all the money and not enjoying the looks of it?
<Not in my opinion, no. Again, unless the life you place needs deeper, I'd settle for a minimum of substrate elsewhere>
I will have all displays stocked full of live rock as well as the sump.
(Besides a top of the line skimmer -- I really don't want a lot of machines running to dose things....I want to keep it simple and natural with macroalgae and water changes as my main tx's. If DSB's in all displays are going to be a wonderful way to assist me in keeping the tanks healthy and as maintenance free as possible -- I would do it).....
<Understood>
2) In the display tanks -- you mentioned I could use a shallow or aesthetic depth. What would that be? 1/2" to 1" ? ( I am afraid I don't like shallow look either -- I like the 2" depth look ..... :(
<Less is better>
So in the displays -- is it either I pick a shallow depth or go with 4" ( or higher) -- but no in-between depth?
<Ideally, yes>
2) You mention that I did not need to buy the 2400 lbs of sand -- if I had "other means of providing biomineral and alkalinity... and your livestock doesn't require such..." I am not sure if I will have other means going -- I will have all the tanks and the sump stocked with live rock -- does that cover me for the biomineral?
<That and salt mix change-outs, likely so. You should test... determine if the biomineralizing life, metabolism here, and reductive events in these systems need "boosting" w/ supplements, reactors>
As far as the alkalinity -- I have to dose now upstairs tanks every day for KH. I use Instant Ocean /IO reef crystals....Will DSB's eliminate the need to have to dose KH so much?
<Only time, measure can/will tell. Should be much less for a considerable period of time (months to years)>
These upstairs tanks are reef tanks too-- just as the downstairs will be.....Does a DSB help with having to buffer for KH so frequently?
<Oh yes>
Thanks Bob. I appreciate it!
<Certainly welcome David. BobF>

Sand or crushed coral, 3/5/11
Hi, I am going to be setting up my 72 gallon tank soon that will eventually be a reef system. In my first tank I started out with sand but thought it ended up looking nasty with fish poop and whatever then I switched to crushed coral I think it did look better.
<My guess is you have inadequate water flow, detritus should not be building up on the sandbed.>
When I set up this tank I want to be pretty top of the line which would be better the crushed coral or live sand, I read that crushed coral would make phosphates and other problems.
<Sand is generally preferred as it will trap less detritus and make for a cleaner tank.>
Also do you need a refugium and what exactly does it do?
< http://www.wetwebmedia.com/ca/volume_6/volume_6_3/refugiums.html .>
Thank you,
Angela
<Welcome>
<Chris>

DSB or BB, Deep Sand Bed Utilization 3/5/08 Hi Guys! <Hello> What would happen to the hobby if you were not there! <Probably see a few more sharks shoehorned into a 20 gallon tank.> As again I come back to you. I have 36"W x 30"B x 30"H reef supported by a 36 x 12 x 12 sump with a filtration using sponge (NO BIO BALLS). I have approx 80Kg of LR. I always faced a problem of high No3. Hence 6 month ago I decided to go bare bottom on the same tank. Today I again face the same No3 problem. So a friend of mine suggested I go for a DSB like his (wherein he got 100Kg of sand from a beach for his DSB) and add another 20 Kg of LR which he has spare with him. I was thinking of doing the same. But this time I want to make sure that my no3 issue is resolved once and for all. <The nitrate issue is often caused by overfeeding and too infrequent water changes, while a DSB can help, its not a magical bullet.> It also crossed my mind that the LR I am using could be faulty too. So my questions are: 1) Should I go for DSB or a BB is better? <Its a matter of execution really, but I use a DSB.> 2) Should I go for a complete new set of LR? <If it is more than a couple years old I would think about switching out maybe 10%, but no need to replace it all.> 3) If a DSB is the sand from the beach (clean) suitable? Thanks in advance Regards <Chris>

Playing In The Sand! Bob: <Scott F. here tonight> 55g FOWLR, 2 Tangs, 2 Perculas I am going to convert my crushed coral substrate floor to a nice white sand (can you recommend a type/brand?) <I'd recommend any of the Carib Sea oolithic aragonite products, like the "Aragamax Sugar Fine Reef Sand".> My procedure will be to move my LR to one end of the tank, then scoop out the CC by hand until half of it is gone, then add the sand, move all the LR back on the sand floor and repeat the process at the other end; how does this sound to you? <Sounds okay- but if you're replacing "live" sand with dry, "dead" sand, I'd do it in thirds, changing out 1/3 per week, to allow some time for bacteria to colonize the new material. If you do it all at once- there is a good chance that you'll experience an ammonia strike due to a high percentage of your tanks biological filtration processes being disrupted> If that's ok, how would I go about actually placing the sand? I mean do I dip the bag down to the bottom and slowly pour it out or what? <The classic, "clean" way to do this is to pour the sand through a wide diameter (like 3- 4 inches) piece of PVC pipe, cut slightly taller than the depth of the tank. Easy!> My purpose for doing this (to make sure I'm not off base) is stop the detritus accumulations in the substrate and also for nitrate control) <Then you're gonna want to go for at least 3, and as much as 5 inches of sand. You'll notice a great difference in nitrate once the sandbed gets established!> Many thanks for your help! <Our pleasure! Good luck with this project! Regards, Scott F> David

Playing In The Sand (Pt. 2) Scott: <At your service!> PVC idea worked great! Easy as pie! Boy that sand looks a million times better than the coral rubble... course it looks a little weird at the moment as only half the tank is done - kinda like a beachfront almost <Hey- nothing wrong with that! LOL> - I went somewhere between 4 and 5 inches in depth... Looking forward to next week! <Yep- take it slow...You'll appreciate the results of being patient> (One week is enough time to allow the sand to become "live"?) Thanks heaps! <My pleasure! Good luck with your new sand bed!>

Aragonite sand - 2/15/03 HI Bob , <Anthony Calfo in your service> Is Southdown sand considered fine sand? <yes... sugar-fine oolitic/aragonite> and is it good to use for a DSB. <the best in my opinion at 4-6" or more> I have a fifty five gallon tank with about 3 inches of Southdown sand. <That would be the minimum for efficient denitrification IMO> Some corner areas are turning black . Is this normal ? <Yes, likely... unless you notice a sulfur smell (rotten eggs) which often indicates a lack of good water flow and/or stirring in the tank> .Tank has been running for 4 months. <Ahhh... no worries, the tank is too young to go anaerobic without extreme neglect (not likely here). The coloration between the glass in sand is limited to that thin film/area and is from indirect light causing dark algae> I was going to raise this to 5 inches this weekend . Do you think this is a good idea or should I leave it the way it is and get more sand sifters? <Both if the sand sifters are hardy (like bullet/dragon gobies or blue-spotted yellow watchman gobies> Thanks Chris <best regards, Anthony>

Substrate depth/marine Hello Mr. Fenner, One last question, Heheheh..... Flying Fish Express suggests that I purchase about 90lbs (3") of substrate for a 55 gallon tank, preferably Aragonite (or 60% Aragonite and 40% live sand). I think I remember reading on your site that a 1" of substrate will do fine (that's if you don't have a UGF). What do you recommend? thanks, Greg <The one inch will be fine. Bob Fenner>

Southdown vs. other sands - 2/21/03 Sorry to bother you again <no problem.> I've got a local ace hardware mere blocks from my house and my question is this IS there a difference or something special about the Southdown play sand that makes it preferable to other "play sands" the ace near my house carries their own brand of play sand, could this be used just the same? <Not the same type of sand by a long shot. Please look through the WetWeb google search tool as this topic has been covered many times here. Use Southdown as the keyword. There is some really great information there. I would not use the Ace Hardware over the counter play sand, if it were me.> It's $2.99 per bag, not that that's relevant LOL.<Yeah......it's just money! Who cares about that?!? Paul>

Re: Southdown vs. other sands - 2/21/03 ok thanks, <my pleasure> I will have to get some from the shop then, as the home depot near me doesn't carry the Southdown. <yeah, same here. Are you on the West Coast? This stuff is mined in Florida and seems to only be distributed on the East Coast for the most part. Of course, there are always exceptions to the rule. Sorry to hear that Southdown is not available in your area. Check out the links from the search. Interesting stuff there. You can always see if someone can freight it for you. Check around the forums here and at other sites as sometimes it is offered there. Good luck! Paul>

Substrate depth on new tank Hi guys, <Hi Greg, Don here today> I have a quick question regarding Marine Substrate? I've got a 55 gallon tank with about 45lbs. of live rock and about a 2" layer of Aragonite across the bottom. Is this too much? Is it too late to remove some of the sand? The tank has been cycling for about 2 weeks now. Also, would it be beneficial to place the live rocks on some eggcrate? Thanks in advance. <Well the recommendation is for less than 1" or more that 4". You do not say what the end game is here so some assumptions have been made. Since the tank is brand new, I think I would remove some substrate and try to sell it to a fish buddy, or save it to replace your substrate down the road (store dry and as air tight as possible). This may add a week or so to the cycle process, but remember: good things are worth waiting for. I do not believe it is necessary to put the rock on eggcrate for long term. Don> Regards, Greg

Crushed Coral Depth? I have had my SW tank for 9 months and have been adding live rock (now 52lbs in a 55 gal tank). Reading your web site and others this past week I became concerned that my 55 lbs (Carib Sea, Florida, 5-10 mm) crushed coral substrate was too thick (approx 1.5 - 2 inches) - I am not using an UGF and the articles mentioned to keep the substrate to 0.5 - 0.75 inches in this case as it mentioned a couple of gases that can develop that are toxic to the inhabitants (fish and corals). This morning I read an article on your site that encouraged a thick bed (see excerpt below): Substrate question I have about a 2.5 inch bed of crush coral in my 55 gallon tank. I want to add another inch of Flamingo Pink on top of the crush coral, is this OK or will it kill a lot of my biological in my crushed coral? Also would the Flamingo Pink be ok with gobies (stirrers). Thanks, Jim >> Should be okay... density, size wise of the new/old substrates... with the gobies as well... but will the two mixing together be okay with you looks wise? They will. Bob Fenner QUESTION: Can you please tell me what the best approach is as I am very confused on how thick the substrate should be. <Well, there are lots of different opinions here. The prevailing thought is that sandbeds (or gravel beds) under 3 inches in depth are too deep to be fully aerobic, and too shallow to foster complete denitrification processes. With coarse substrates, such as crushed coral, there is the added concern of detritus accumulation. With proper substrate maintenance, and the possible inclusion of sandbed "stirring" animals, this type of bed can be successful...just keep an eye on things> I am also sharing the rest of my setup for any general comments/feedback: 55 gallon 52 lbs live rock and crushed coral substrate Magnum 350 Canister with 2 BioWheels (2) MaxiJet 1200 and (1) PowerSweep 228 Coralife Power Compacts 260W (Actinic and Daylight) Skimmer - Prizm Supplements: SeaChem - Calcium +3 (Saturday), Buff (Sunday), Trace (Tuesday), and Vita (Thursday) Feed only frozen foods (varied) QUESTION: SeaChem Reef Success Calcium +3 is easy to add, but is this a Calcium Chloride rather than Calcium Hydroxide? Should this concern me enough to change this to something else (Kalkwasser, B-Ionic, Kalk, etc.)? What do you recommend? <Not familiar with this particular product, although I think SeaChem makes some excellent ones. You may want to contact them regarding the specifics of the product's application> Livestock: Rabbitfish, 2-Percula Clown, 1-Purple Firefish, and 1-4 stripe Damsel Janitors: Serpent Star, 2-Emerald and 2-Red leg Crabs, 11-Snails (Astrea, Bumble Bee, Turbo, Margarita) I will start to add coral over next few months and a Mandarin Goby in another 3- 6 months. <I'd avoid the mandarin altogether in this tank, to be perfectly honest. To many competitive feeders. Although I commend you on holding back on adding the fish until your tank is further established, I think that it's really a fish that needs a setup dedicated to its specific needs and dietary preferences (like amphipods and copepods)...> QUESTION: Any feedback you have on this setup and the direction I am going in will be greatly appreciated. <Sounds okay so far. You didn't mention anything about maintenance procedures...I'd utilize smaller (5% twice weekly) water changes in this tank, to really get to nutrients before they have the chance to accumulate and degrade the water quality. Also, you may question yourself on te use of the vitamin and trace element additions...If you are conducting regular water changes, you are usually replenishing these substances in the process. If misused, these products can lead to nuisance algae blooms. Finally, make sure that the skimmer is cranking out at least a couple of cups of dark, yucky stuff a week> Thanks for all your help - both with the questions above as well as your extremely informative web site - it is a tremendous service to the hobby! <So glad you find it useful! It's our pleasure to be here for you! Keep reading and learning, and enjoy your tank! Regards, Scott F>

Substrate A real quick ? The dude at the fishy store told me the best substrate is sand with perhaps a small amount of live sand in my 75 gallon tank. Right now I have 1/2 crushed coral and 1/2 crushed Aruba Puka shell. He said that this may cause a problem with Nitrites...is this true? Should I go with sand? If so - how deep? Thanks for your help! Jeff Wagner <Please read here: http://www.wetwebmedia.com/marsubstr.htm and the linked pages (in blue, above) re your questions. Bob Fenner>

Make A Sand Decision Hi Bob, I wanted to get your opinion on the great sand debate. <Actually, Scott F. here today> I have read dozens of opinions on using normal play box sand from HD (by Paragon), all negative. However, not one of these people admits to ever having tried it, they just all "know" it's bad. Do you have direct experience with this or a similar product? It seems ridiculous not to use it if it's actually OK and only "folklore" is stopping us. What do you think? <Well, there may be some merit to the opinions. I personally have not used this product, but I have used the infamous "Southdown" play sand, and it works quite well. It is an Aragonitic product, and provides a lot of good benefits (calcium supplementation, proper grain size for denitrification, etc). I have heard that many regular play sand products contain a lot of impurities, ranging from metals to silicates, so what appears to be a great "bargain", could actually be an expensive mistake! Do check with the manufacturer, if possible, as they may be able to give you some idea as to the composition of the sand. Hope this helps! Scott F>

Substrate Hi guys, Bryan here, it has been awhile. I have a few questions. First is regarding substrate. Setting up a 75 gallon FOWLR. In the main tank am going to add 1/2"-1" of Carib sea Arag. sand. Adding a 20 gal tank under the stand for a DSB w/ more LR. Is it alright to use the sand for a DSB or better to use s/t like special grade reef? <Better to use the fine grade of sand. I have the Special Reef Grade and do not like it/do not recommend it.> Also I read on the F&Q that I can set up the 20 gal refugium w/ DSB and LR w/o any lighting. Is this fine if I decide to go this route? <Yes, is fine for cryptic animals (sponges, etc.) but adding lighting would diversify the refugium.> Last question. I am looking for egg crate to go into my sump and can't seem to find any. If you have any suggestions please let me know. <Most any hardware store. It is used for overhead fluorescent lighting fixtures.> Thanks Bryan. <You are welcome. -Steven Pro>

Re: Sand & Stars Hi, thanks for your prompt answer. <<Hello, you are quite welcome.>> In your mail you said that "perhaps it's time to put a little more sand..." but Anthony says "5 inches or more or 1" or less... right now I have a 1/2" - 1 1/4" from the front to the back of my tank... <<I had to call Anthony on the phone to make sure we both sing the same song. To clarify without putting words in his mouth, it is his observation that an inch or less is a zero-sum; no harm, no benefit. In between one and three inches is certain disaster - the sand bed will be neither anoxic or anaerobic. Something between 3 and 6 inches is best advised - three is great, four is better, five even better and so on.>> So I think I will run for a Brittle star... (one? two? <<depending on the size, one, perhaps two, no more.>> my tank is a 200 ltr with sump) My actual animal inventory is: 1 damsel yellow tail, 1 damsel blue devil, 1 tang, 4-5 blue legged hermits, 4 Turbo snails, 2 little peppermint shrimp, 1 banded shrimp. nothing will fight with the Brittlestar?? <<There aren't many things that 'fight' with brittle stars, the seastar would bail out rather than fight.>> Thanks again. Carlos <<You are quite welcome. Cheers, J -- >>

Crushed coral to sand Hi Bob and thanks for your info on my copper problem...here's another one for you. I just decided today that since I'm going to have to get rid of my copper filled crushed coral, <very wise> to upgrade some and I have a question for ya. I purchased a Amiracle wet/dry filter and am going to get rid of my under gravel filter and go with a sand bed. How thick should I go with the Arag-alive sand. <IMO the so-called "live" bagged sand is quite unnecessary if for no other reason than price. At best it has bacteria in it... does that mean the sand simply wasn't washed before it was bagged? It certainly doesn't have zooplankton, polychaete worms and most of the things that aquarists regard as desirable components of live sand. For that you can get a handful (literally) of live sand from an established aquarium (LFS, aquarium society member, friend, etc) to inoculate a bed of cheap dry sand and all will become live very well in as little as two weeks for a lot less money (and not supporting a misleading practice)> I have two tanks I'm going to do this with...the first being a 110 gal and the other a 55 gal. Thanks Robert <the depth of the sand depends on your purpose and the livestock kept. Small fishes and reef aquaria where denitrification is desired will want more than 3 inches (ideally 5+) of sugar fine media (like Southdown sand from Home Depot... see message boards). For large fishes, messy fish or frisky foraging/burrowing animals the sand bed may need to be rather shallow (1/2 inch) and denitrification accomplished through other means including extra water changes. Best regards, Anthony>

Southdown Sand Which Home Depots have Southdown sand. Home Depot near me do not. RGibson <<Greetings Ralph... Home Depot has a ridiculous number of stores around the country and there's just no way for us here at WetWebMedia to keep a tally of who keeps Southdown sand in stock. Your best bet would be to either ask this question of Home Depot directly or perhaps pose this question on our forum, http://wetwebfotos.com/talk where you can get a diverse set of opinions. Cheers, J -- >>

Lava Rock and other stuff. Hello guys, how are you today? <very well, my friend... I hope you are well too!> I'm setting up a 60 Gallon Marine Tank. It will measure 123 Cm. x 51 Cm. x 36 Cm. I will put two 40 watt bulbs (1 actinic and 1 daylight) and I'm planning on making my own sump instead of buying a Tidepool 2. The pump I will be using is a MagDrive 1250GPH. ( I think this will be enough) <indeed enough water flow but perhaps add more daylight tubes in the future for light> I found two bags of lava rocks in my house, you know, those used for the charbroilers? I already boiled them in water and now I have them in a plastic box with salt water, an air diffuser and some Stress Zyme each day, to colonize the bacteria on them. <whoa!... don't put them in the tank and don't bother buying such enzyme products at all... rather a waster of money for most> Today, a friend told me that lava rocks are the worst for marine aquariums, because they have heavy metals and toxins. Is this true? <yes... it may very well be true. Indeed some risk involved here since lava is volcanically formed. I would never recommend it. Carbonate material is always better> I even have a very good book that tells me that they are the best. I'm only planning to put them in one of the media bays in the sump, because in the aquarium I'm planning to put normal live rock. What should I do? What is the best biological filter for the sump? <if you use it... I don't think it is likely to kill animals, but may impart nutrients for a terrible nuisance algae bloom> What can you tell me about the bed? What kind of sand should I use and how deep? <less than 1/2" if just for aesthetics, 4+inches of sugar fine aragonite sand if you want denitrification> Is the SEACLONE skimmer good? <it has a BAD reputation with aquarists> I live in Venezuela, and stuff here is very expensive. This skimmer that in the US costs $99, here costs $230. <my goodness! Many folks here wouldn't even take it for free let alone pay good money for it! What other brands are available to you?> Is it possible to put it in the sump? <there are many models that can go in the sump> My LFS tells me that keeping the salinity at 1.019 will keep the Ich off and other parasites and the fish live happy. Is this OK??? <it is OK but not exactly true... the lower salinity is more favorable to the fishes and less favorable to the parasites, but there is no guarantee that it will prevent Ich. My friend, you really must have a small quarantine tank to all new fish, rock and invertebrates in first. Please read through our WetWebMedia site for advice on QT protocol... it is critical to success. Please never put a new animal directly into your tank from a LFS or anywhere!> what are your suggestions? Thank you very much for your time. Julio Grossmann <with kind regards, Anthony>

I was born to Rubble What a great crew. You have one of the best jobs in the world. <Yes, agreed... does not feel like a job at all> You didn't drive to/from Dallas did you? Damn, if you did and I had known, I would have asked you to pick up my fish tank I have in storage there. :) <Ha! Did drive... and would have picked up (was some 400 pounds lighter on the return> Sigh. What did you leave in Dallas? <Four hundred pounds of Korallith, some calcium reactors and books mainly> When you have time, if you can dig around for pictures that show the Firefish environment I would love to see them! <Mmm, good question... maybe I can use your request as a springboard for a column...> Oooh, a rubble zone article -- yes, yes, yes!!! <Call me Barney (Rubble!)> Okay, here are some questions: How deep should the rubble be? Should it be just a single layer, or towards the back of the tank should rubble be put on top of each other for several layers? <Large, chunky bits on top... finer materials down first> Do different soft corals grow near each other there or is it rather sparse? <Mixed... some species near, most are spaced a width of a colony apart or more> If only one softie should be included, should it be only one coral that is allowed to grow huge, or should it get fragged and put in several different spots in the tank? <Depends... on what you want to do (culture, cuttings), but do start all smallish, spaced apart> Should the softie (colt, finger, toad stool, whichever it is) be on a bigger piece of live rock, or should it be on the very bottom of the tank, getting a foot hold in the rubble? <Species dependent as well as what you want to look at.> Okay, if I read correctly last night, you think an inch or two of sand covered with rubble would not cause Cyano or algae. Wouldn't it be a nutrient trap because debris would get caught and then decay in the sand rubble? <Not much... in a vivacious growing system, there is little nutrient to uptake> You could always try staying up all night and then all day... <Too old... have memories that used to be able to when I was a pup... but probably just dreamed that bit up. Bob F> I know I could do that ten years ago! MM <Ha! Make that your age back for me. Bob>

Rubble Zone Tank Hi Bob, <Hello Madison> How was your Indo trip and MACNA? <Fabulous on the first, and just back and shaky from driving to and fro to/from MACNA... it was very nice> I've been thinking about the rubble zone tank... I'm not sure if it can work. <Why not?> If I take 1" of sand and then throw in rubble found in dealers tanks and hammer live rock into little pieces to create rubble over the bottom of the aquarium, what would be my biological filter. <Yes...> Not the sand, it will not be a DSB. A DSB would not work with rubble everywhere, it needs to be open. There would not be as much live rock as in most other tanks, so the rock isn't going to do it. If I did it this way, would I just be creating a great environment for algae blooms and Cyanobacteria to thrive in? <Not likely> If I didn't put the rubble in and went with a 4 - 6" DSB, well, it wouldn't be a rubble zone anymore. Any thoughts on making a rubble zone work? <As they say in the Nike ads, "just do it"... am sure the rubble by itself and likely with deep sand would be fine> Do you still have jet lag? <You are like myself... "para" sympathetic, yes... still not "caught up"... and suffering for it. BF> MM

South Down Sand Dear Steven Pro, Thank you for your quick response! One Last question, today I purchased 8 bags of the Home Depot Southdown sand and once home, I noticed the following changes as underscored. Soft Texture Sterilized Silica Free Not recommended to traction or aquarium use Everything else is identical including the SKU. Are you aware of this change and should I be concerned about the statement saying that it's not recommended for aquarium use. <I have eight bags myself sitting in the garage, so I went out and looked them over for the disclaimers you have seen. Mine only say that the sand has been sterilized. The silica free statement is a good thing. I have no idea what soft texture is, but the "not for aquarium use" sounds to me like a legal disclaimer or something they added to appease the other companies that sell/market their sand. I would not worry about it. I do not remember if I mentioned it previously, but I would sift the sand. I have found pieces of quartz rock in the sand. Southdown packages a lot of other materials for landscape use and there is a possibility of other things slipping in. Again, nothing to be too worried about. The stuff is so cheap, any potential risk is far outweighed, IMO.> Thanks again, Ron Allard <You are welcome. -Steven Pro>

DSB substrate question Good morning (or maybe noon, if you're east coast), <It is now the afternoon here.> I'm building a DIY refugium with a DSB. I've seen you recommend Home Depot Southdown sand before. I went to my local Home Depot and they did not have anything by that label, but they did have "playground sand." It was sugar-fine, composed of crushed marble, taken from calcite ore. <You do not want calcite. It does not dissolve nearly as well as aragonite. There was a very good article in the October 2002 issue of Tropical Fish Hobbyist by James Fatherree discussing the differences.> It was labeled as over 99% silicate free. Is this essentially the same thing as Southdown? <It does not sound like it.> Would this work for a DSB or should I consign myself to the high prices of my LFS? <I would continue to search for a better product. There are several online vendors now selling Southdown like sand. I would also ask a local marine aquarium society. They could probably direct you to someone that sells Southdown or a similar product.> Thanks for your counsel, John <Good luck! -Steven Pro>

DSB substrate question Good morning (or maybe noon, if you're east coast), <Ahh Hi John, West Coast, a fine sunny morning!> I'm building a DIY refugium with a DSB. I've seen you recommend Home Depot Southdown sand before. I went to my local Home Depot and they did not have anything by that label...but they did have "playground sand." It was sugar-fine, composed of crushed marble, taken from calcite ore. It was labeled as over 99% silicate free. Is this essentially the same thing as Southdown? <Hmm, don't know if this is crushed marble or coral? There are several versions from Southdown of Caribbean aragonite sand. Some is labeled "Southdown Plays and" and some "Playwright play sand". You are looking for Caribbean aragonite, "mined" from the Caribbean. Also, look in the Garden Dept, not the concrete dept where they will send you for sand. If the bag is from Southdown (on the back label) you can confirm the contents by calling Southdown at (800) 526-1753.> Would this work for a DSB or should I consign myself to the high prices of my LFS? Thanks for your counsel, John <Yes. It will work fine. You may also seed it with "live" sand from your LFS or LR. Go for it, we can't get it out here! Craig>

Substrate for big Australian tank and Seagrasses Hi Anthony <cheers, mate!> I'd like your advice on suitable substrate/s for our 600,000L display tank, <glad to share an opinion> remembering that the water depth will be six meters and the habitats we're to show are sand, coral, seagrass and rock. In Shark Bay there is a small bivalve (Fragum erugatum) which proliferates in the hypersaline areas to the extent where its empty shells are harvested and sold in large quantities. The processed shells are typically 8mm diameter, hard, white and I assume composed of calcium carbonate. <yes... some form of calcite> Recently the processors have been crushing this shell to a 1mm to 2mm grain size and selling it as an aquarium substrate. I was thinking of using the same crushed substrate in our tank for the "sand" and some of the "coral" sections. How thick should I make it here? <that depends on your intent and to some extent the livestock. If you have no other means of denitrification and will consider a deep sand bed methodology in the display proper, then we need 15-30 cm bare minimum. And in such a large display... I really must say that 30-60 cm would be quite nice. The advantage is that it will provide natural plankton (nanoplankton, bacteria etc) and naturally denitrify will little support. The disadvantage is that it could be a liability with inadequate water flow and become a nutrient sick and support dreadful nuisance algae. Nuisance algae could be further mitigated if the material is rich in silica, which as a mollusk it is quite possibly so. My advice is to get a assay of the materials composition and compare it to a known "safe" substrate commonly used by aquarists or public aquaria. That will tell us first if we can even continue to consider these crushed shell as a candidate> Do you think this substrate would also suit the "seagrass" section, or would it need to be finer than this? <I must admit... I am somewhat concerned that this is a little too course for seagrasses and good denitrification (if the bed is shallow). Here in America, we commonly culture Thalassia and Syringodium (some Zostera too) in muddy fine substrates ranging from .2 to .5 mm> I would like to grow local species of seagrass and notice that the natural substrate is a lot finer than this, and more silicon-based rather than CaCO3. <interesting about the silica. I'm not sure if it is utilized or simply tolerated by the grasses though. Still... if the course media is to work at all... I am sure the grasses will need to be planted rather deep... 8cm minimum.> Would I be better off using the same substrate as found in the bay, or would this silicon-sand be likely to encourage diatom blooms? <indeed... I'm concerned about excess silica in a closed system where large water changes are not convenient if necessary> Perhaps I could have some of the shell substrate crushed a bit finer if this is important for seagrass. <if possible that might be ideal. Do know too that the dry substrate will need to age for some months before it can support the seagrasses. When you collect the grasses, you will need to collect them like plugs (large cored berths) if you are to have any chance of successfully transplanting them. Perhaps you can just take a little extra natural substrate with you and seed the dry crushed shell in those few spots where grasses are planted early while we are waiting for the rest of the bed to mature and the grasses to spread> I notice many seagrass species have roots that penetrate at least 300mm into the sand. Should I make our substrate in the "seagrass" section this deep? <it does not have to be quite this deep in my opinion... but they do need deep beds and anoxic conditions. Hence the need for deeper substrates if you use courser media (the course media allows better/unwanted penetration of oxygen rich water)> Is it possible to have the substrate too deep? <not likely at all... if you said you wanted it 90cm deep, I would have no complaints!> One other thing I have noticed is that the sand in the bay seems to be quite nutrient-rich - when you dig down 100mm or so it becomes a grey color rather than white and smells rather organic. Do seagrass species use nutrients in the soil for growth, or are the nutrients obtained from the water as for other marine plants? <they derive nutrients from roots, stems and leaves... but a rich substrate is quite important> If the soil is a major source of nutrients, do I have to enrich my substrate before it will support seagrass? <yes... recommended here as per above with this soil buried in little pockets where you first transplant seagrass plugs> Our construction is still going forward, although rather slowly. <all in good time... like fine Australian wine :) Ahhh... if only I were sipping Shiraz/Sirah right now!> At least six months until we can put water in it. Gives me plenty of time to learn all these important things :) I'll send more photos when the tank is at full height. <excellent, my friend. I'm looking forward to it!> Thanks again Pete McKenzie <Pete, do look over these links for advise on transplanting seagrasses. Some very good information on harvesting and transplanting techniques. http://chl.wes.army.mil/library/publications/chetn/pdf/cetn-v19.pdf and here: http://chl.wes.army.mil/library/publications/chetn/pdf/cetn-v11.pdf With kind regards, Anthony>

DSB, etc. Hello again: <Greetings!> So, I read info on your site about LS and DSB's until I was bleary-eyed (and still have not finished). I then went out and bought some Southdown Tropical Play Sand that I saw mentioned. Then I realized after putting some in, that 4" is a whopping 20% of my 55gal tank depth. WOW! <It is a trade off for everyone.> I was surprised it was so DEEEEEP. I already suffer from tank envy, and the thought of losing that much height pains me. I read on your site that someone had a 29gal, and your crew said that they probably would not need it so deep because of the lack of size. Is there a more accurate sand-to-depth percentage to use as a general rule that may be better? <Not that I am aware of...either very thin, like less than an inch Or deep with 3 inches on the shallow end of DSB and 4 inches + even better> maybe a surface-area-to-depth? <I've personally never heard of anything like that. DSB's are somewhat controversial, therefore opinions differ. Compare the DSB idea to the concept of a Berlin tank. They are the exact opposites yet many experts believe DSB's are the only way to go...just as many think they are just a nutrient sink. You must read/learn and decide for yourself. I had to make the same decision for my tank.> I did not catch any info on that on your site (yet). If AQ <AQ=Aquarium?> husbandry success is truly on a case by case basis (isn't it?), <Quite frankly, people that are serious enough to read/learn about water management, disease, stocking, etc. and buy a few books will be successful in this hobby. It is the people that buy a tank, put in salt water, and start throwing in critters that leave this hobby with their wallets lighter and a chip on their shoulder. You are well on your way to being a success. Keeping learning.> How would I know without trying lesser depths that it is working or not? <The differences will be subtle either way.> Also, I read you can siphon out your old CC substrate instead of the messy way. <Not if the CC is really big pieces. Small pieces the size of freshwater gravel will siphon out easily. Just get a cheap gravel vacuum and hose from any good fish store. Buy the largest size you can find.> Is this by using gravity alone? <Yes!> What thickness of tubing would I need? <See above.> Thanks for your helping "the new guy". <Don't worry my friend. All of us were new once! There a lots of differing opinions in this hobby. You need to read everything available and then decide what makes since for your aquarium. You're on the right track! Knowledge is power! David D.>

CC vs. LS I recently had a 72 gallon reef-ready bowfront FO tank set up last week. I am cycling it with 9 damsels that have been in for about 6 days. Here are my questions: I currently have a substrate consisting of crushed coral. I have heard several people say that sand is a better substrate. Is this true? <It all depends on what purpose you hope the substrate will serve. If you want the substrate to look good and help buffer the water, crushed coral will be fine. I would caution against having a deep bed of CC because it will become a nutrient sink in short order. Use a thin layer only. In a reef tank, sugar sized sand will slowly release natural calcium, help to buffer the PH, and if the bed is 4 inches+, it will aid in nitrate reduction.> Is it better than CC? <IMO not for your situation. For a reef tank? Yes.> Also, I have heard people say that you don't have to vacuum sand. Is this true? <We don't vacuum sand the same way we vacuum CC, that's for sure! The sand will quite literally vacuum right out of the tank. But you will need to very gently vacuum the surface of any obvious debris when cleaning the tank. If using sand be sure to either have a thin bed (one inch or less) or a thick bed (4+inches) of sugar fine sand. Otherwise you will create a nutrient sink> If I decide to change the substrate, should I wait until the tank has cycled? <Either way you're going to interrupt the biological process happening in the tank if you remove all the substrate at one time. I suggest taking a little out at a time over a period of a few weeks. Slowly add the new substrate as the old is being removed.> What is the best procedure for doing this? <See above> Thanks for our help. Jerome <My pleasure Jerome. If you haven't perused the wetwebmedia.com website, please do so. The site contains thousands of articles and facts and issues relevant to the keeping of saltwater and freshwater fish. Have a nice evening! David D.>

Live sand question Hi James the salty dog or whoever reads this, <Hi Shawn> I looked over the link and asked my local fish places about it and have decided to just go with sand only. I have one last question regarding the live sand. I remember reading one response, I could've sworn it was on page one of the live sand questions and I've re-read both FAQs twice now but I can't seem to find it again. I thought I read on one of the responses that it is ok to buy play sand from home depot to use in your aquarium and to seed it with some live sand or live rock. Is this still ok or has it been found not be safe now or anything. Sorry one more question, the live rock I'll be getting for my tank is most likely going to be uncured and since I'll have an empty tank and I plan to cure it in the tank would it be ok to just add the sand while it's curing or should I wait till it's done curing and then add the sand? <Problem with that is with all the die- off from the rock, it will be harder to vac the crud up with the sand being in there. James (Salty Dog)><<RMF would like to throw in a point here... HD sells both a near-pure silicate "Play Sand" and a "Southdown" product that is almost entirely carbonaceous... there is very little silicate content in the Home Depot Southdown product... this last should work fine.>>

Sea Sand Bed - South Africa 3/30/05 Hi guys & girls fantastic site!! I have a question: in about a month's time I am going on holiday to our eastern coast of South Africa (Durban). I currently have a 400litre tank with a medium depth sand bed consisting of crushed coral and aragonite. I was wondering if I can bring back some sea sand back from the coast to give my live sand a boost. The sand by our coast consists mostly of just plain sea sand and crushed shells. Can I use this, isn't it too fine in size ? What do you recommend? Thanking you in advance. Werner Schoeman <There are many caveats to this. Temperate animals will not survive long in your tropical tank. Also, temperate sands may not be coralline in origin, so they won't add to buffering capacity and may contain undesirable elements. Pollution is also a concern. "Live sand" is (or should be) collected off shore in tropical regions near reefs. Best Regards. AdamC.>

Just How Small Is This Place!? II - 04/28/05 Thanks Eric. < Most welcome. > Also, I recently got rid of my sand substrate because it just seemed to give me problems with making parasites linger in my tank. I want to get a fine gravel type substrate. Would dolomite and crushed coral be comparable? Do they have similar benefits or is one better than the other? < Crushed coral is the better choice, aragonite even better. > Couldn't find anything about dolomite in the FAQ'S. Thanks again. < Regards, Eric R. >

Marine sand source Hello to all, My quest for sand continues. As the company that produces Southdown sand is no longer in business and the only place in the United States that still has some is in the central states I have found another possible source for sand and would like your help. :) There is a company in Monterey that dredges up sand from the bay. They sift it and kiln dry it and package it for sale. The lady I spoke with today says it passes a through a 20 ?? sieve. <A physical sizing... twenty average grains lined up end to end would equal an inch... about this size will fall through openings in such a strainer> Is this something that would work in a reef tank?? Thank you, David <Mmm, likely not... probably is largely silicate based... Please read here re: http://www.wetwebmedia.com/marsubstr.htm and on to where you lead yourself through the linked files at top. Bob Fenner>

A Million Grains Of Sand...Free For The Taking? Hello, <Hi there! Scott F. here today!> We are heading to Jacksonville, Florida for a week this summer. We are staying at a family friend's house on the beach. Is it possible to use the beach sand in our aquarium? Brian <Well, Brian, this is a pretty common thought for us crazy hobbyists...I mean- why not? It's right there...it's free, it's...well- actually- it's probably a really bad idea! Besides the fact that beach sand is a fairly precious natural resource (in my area, the sand at local beaches helps prevent erosion, and this is really important!), sand collected near or on shore could contain all sorts of potential pollutants, ranging from simple organic silts to possibly toxic chemicals or agricultural runoff. Most of the packaged sand that we buy at the LFS is not beach collected, so it is generally free of these potential pollutants. Personally, I'd resist the temptation and fork out the bucks for pre-packaged sand. Enjoy your vacation! Regards, Scott F.> Sand Hello and thank you for all you do :) <You're welcome> I have been reading about Southdown sand and what I have found is this. Their supplier went out of business so they don't have the tropical play sand anymore. I tried Quikrete and Basalite and their products are not aragonite. Do you have any idea if there is anyone selling sand at decent prices. I just spent $200 putting sand in my 100 gal refugium and now have to sand my 150 gallon tank. <David, I've been hearing the sand Home Depot sells is Southdown sand. I'm sure Mr. Fenner will see this and maybe he can confirm. James (Salty Dog)> Help, David

Mystery Sand... Dear Crew, <Scott F. your Crew member tonight!> I know this topic has been covered extensively on your site and throughout the net. BUT... A fellow aquarist and I just ran into a pallet of "Yardright White Play Sand" at a local store. We've been HUNTING for Southdown substitutes all around but of course we cant find it. The bag says that it its made from marble, and we brought our "Vinegar" test kit with us and it bubbles.. so we bought some.... We both want DSBs in our new tanks. I've seen Aragamax, and its not near as white as this stuff. Is this the right stuff????? THANKS! <Hmm...since this stuff is not aragonite based, I wonder about its buffering capabilities and level of purity, despite its apparent solubility. I'd be more inclined to pass on it for this very reason. Do check with other hobbyists to see if they have used this stuff with success, but proceed with caution. Good luck! Regards, Scott F.>

- DSB, Sand Selection, and DIY LR Questions - Hello, WWM Member! It's so nice to have such a great resource to help those of us without a lot of hobby experience. I'm still in the planning stages for a 70-90g peaceful reef tank, and I'm confused on certain points. I have done TONS of reading on WWM regarding these questions, and I haven't found consistent answers... perhaps some of my questions have no conclusive answers! First, regarding DSBs. I know that optimally, 6"+ is best. Is 6" optimal? <Six inches is the minimum, not optimal. Eight to ten inches would probably be optimal, if not always practical.> If not, what's the optimal depth? (I know that making it too deep can cause hydrogen sulfide problems; at what depth do problems develop?) <Not sure this is empirical. I have a 12" DSB sump that's been running for a year and have had no problems with hydrogen sulphide. Think sulphide problem may result from sub-optimal depths, where the proper bacteria that would make use of this stuff do not exist.> I've done a lot of reading regarding substrates, and I'm confused. I've read that Jawfish and other burrowers are best kept in fine sand with some coarse material to aid their burrowing, and that these fish move around the bigger pieces to their liking; I've also read that coarser material mixed in won't harm anyone. However, I've also frequently read that you shouldn't mix substrate sizes so channeling/packing is minimized. So, the question: if I'm keeping Jawfishes, gobies, and the like, what should I do? Should I stick with pure sugar-fine aragonite sand, or add some crushed coral, or add even coarser material like crushed shell? <I'd do all three.> If I should have coarse material, what ratio is best? <Perhaps 1/3 of each.> I just want to make sure they have the best substrate possible. Also, I'd like to make some GARF Aragocrete "Reef Tables" and a couple caves for my tank (I'll have plenty of "real" live rock, of course). I've heard some people have no problems, and others make claims that the cement adversely affects tank chemistry. What's the truth? <The truth is that anything cementacious would need to be cured for a while - months - in a weak acid solution (vinegar would do) to help bring down the highly alkaline nature of cement products.> Would I be foolish to use Aragocrete, or will I be fine? <No... this has been done for decades in public aquariums and the like - is perfectly viable as long as you take the appropriate precautions.> Oh, one last thing, if I may. I plan on principally keeping quiet fishes, like gobies, Banggai Cardinals, blennies, and perhaps a Jawfish or eventually a mandarin (with a refugium, of course). But... I (and my wife) would love to have a yellow tang (Zebrasoma flavescens). Would it be too boisterous or aggressive a feeder to mix in this type of tank? <Would be fine.> I'm worried that the other fish wouldn't get enough food... Also, is there any species of clownfish that could coexist peacefully, as well, or are they too aggressive? <My favorite are the true and false percula clowns - they seems to be the most docile of all the clowns and seem to get along with just about anyone that won't eat them.> Thanks so much for your time and help; I truly appreciate your advice. Scott <Cheers, J -- >

Marine substrate Hello All I want to first say thank you for all the great info on this site. :) Done much research into my nitrate problem and have formulated a solution due to all the great help already posted. Only could not find one last answer. For my deep sand bed is it ok to use sand from an home improvement store? <Yes... if carbonate based... steer away from silicates. Please read here: http://www.wetwebmedia.com/marsubstr.htm and on to the links at the top, till you're satisfied> Oh yeah one last one... My current substrate is of the big variety, yes I know one of the reasons for my nitrates anyway when I create my DSB can I pour the new sand over the existing substrate? Thanks again for all your help, this site rocks Cheers Fargo <Keep reading the links... Bob Fenner>

Live Sand? - 06/20/05 Thanks for that. When you say sugar-fine sand bed you are not referring to live sand? <<Nope. You can use any sugar-fine sand...even silica sand (I can hear you gasp <G>.)...though I confess I prefer to use aragonite when available. Just seed the "dry" sand with a bit of sand from your mates tanks or from the LFS and it will become "live" in short order.>> Also I should put some critters in the refugium as well correct? <<Depends on what you mean by "critters." If you mean amphipods, Mysis shrimp, copepods, bristle worms, and the like...then the answer is yes...if you mean shrimp, crabs, small fish, etc. ...then the answer is no. The latter defeats the purpose of the refugium.>> Thanks for the info you guys rock. <<From this old rocker...Regards, Eric R.>> Local sand I was wondering if sand from a local freshwater sandpit could be used for substrate. I would seed with some live sand. It is in a 1000gal tidal pool/fuge I am constructing. Time is not an issue and I can wait for it to become live sand. Also wanting to use some local stones as rock, porous limestone type. plan to seed the rock with pods etc. will this work. it would cost a small fortune to buy from LFS or online pre- cured, etc. <If these materials are indeed calcium carbonate based you'll be fine. I would ask the folks who run the sandpit the composition of the material there... if it is more than a few percent silicate based, you would be better off seeking out another source... for reasons stated here: http://www.wetwebmedia.com/marsubstr.htm Bob Fenner>

The best sand bed situation? I've been reading your site for days. I cannot find a definite answer on sand beds. <Welcome to the club. Sand beds have to be one of the most debated facets of the marine aquarium community. Everybody has their own opinions and methods, so there really is no "definitive" method of keeping a sand bed.> I have a new 125 gallon all saltwater fish tank. I have 50 pounds of Aruba crushed shells (Puka shells). is this the best way to layer the bottom of my tank. <As they say, there is more than one way to skin a cat. Out of the many ways to go with a sand bed, not any one method is decidedly better, or decidedly worse than the next. You should check out the following wealth of informative links and make an educated decision as to what course to take. http://www.wetwebmedia.com/marsubfaqs.htm http://www.wetwebmedia.com/marsubfaq2.htm http://www.wetwebmedia.com/marsubfaq3.htm http://www.wetwebmedia.com/marsubfaq4.htm http://www.wetwebmedia.com/marsubfaq5.htm http://www.wetwebmedia.com/marsubfaq6.htm http://www.wetwebmedia.com/marsubfaq7.htm http://www.wetwebmedia.com/deepsandbeds.htm http://www.wetwebmedia.com/marsubstr.htm > Do I go an 1" or 4"? Can I, should I mix it with a sand base? Overall what is the depth you suggest I should lay down? <Once again, it is a matter of what you think will work best in your situation.> Thank you so much for your time and response. <Glad I could be of assistance. Good luck, Mike G> Thomas Duffy

Home Depot Sand Response Previously posted:I thought I read on one of the responses that it is ok to buy play sand from Home Depot to use in your aquarium and to seed it with some live sand or live rock. Is this still ok or has it been found not be safe now or anything? ***************** I would like to respectfully disagree with this response. The Home Depot sand that is referred to here, [which] used to be the 'SouthDown" brand, is not silica based sand. It will indeed help with keeping your pH stable. It dissolves in vinegar, silica- based sand will not do this. I used around 300 pounds of it for my tank and it has been doing wonderful for nearly 2 years now. I believe the Southdown name changed to Yardright, but I'm not sure. You can always test it by dumping some vinegar on it. <Thanks, Bill, but you did not mention Southdown sand, and if you were using it for nearly two years, and doing wonderful, why are you asking about it? Seems to me you've done your own homework. James (Salty Dog)><James... this gentleman was chiming in on your previous day's post... FWIW, I do agree with him... the Southdown product is almost entirely carbonaceous, very little silicate content... RMF>>

Southdown Sand James, I'm sorry, I wasn't clear. It wasn't my question originally. I just read it on the FAQ's yesterday and thought I'd pipe in, and share my experience with this fellow and other readers. Home Depot is the only place that carried the Southdown brand that I'm aware of. So when I read Home Depot sand, I assumed he was talking about Southdown. Sorry for the confusion. <Bill, yes it was confusing. Apology accepted. James (Salty Dog)> <<Sheesh. RMF>>

Sand bed Hello All: <Scott> I am considering changing my sand bed from a plenum to a sugar grain DSB. I would like to just add the sugar grain size sand to the existing bed but I am worried about an anoxic situation that will produce sulfur dioxide? <Maybe... but not if the system is otherwise managed properly> I am worried about a nutrient sink with the grain size specific to a plenum. Maybe I should leave well enough alone! Thanks Scott <Maybe. Plenty on plenums, substrates archived on our site: http://www.wetwebmedia.com/ Bob Fenner>

Substrate Selection Hi WetWeb crew, I looked over your other answers about live sand and well my question is pretty stupid and basic compared to everyone else's but I'm really new at this. Anyhow I am starting with a 50 gallon tank (48x12), aquatic ProClear pro wet/dry filter, and I'm trying to decide the best substrate to start with. I plan on getting live rock, but with the live sand I'm not really sure what is best. I like the look of the crushed coral aragonite stuff, but my bf who just recently got into marine aquatics 7 months ago told me that the crushed coral might not be compatible with some life forms? Like if I want to get star fish or gobies or other types of sand sifters. I have looked but I haven't seen anything that says sand particle size affects which critters you can get, except for an ad for this really fine particle sand saying it was more gentle on gobies' gills. Would it be ok to get the crushed coral and still be able to get sand sifters or would the large size of the substrate harm them when they try to sift through it? I also read that the crushed coral is better than regular sand because it buffers your system more, so would that be the best to use or do you guys feel that regular small grain sand is better? Sorry for being so long winded in my question and thanks a bunch!! <Shawn, I suggest you read through this link. It will inform you better on your choice of substrate, more so than I can do here. http://www.wetwebmedia.com/marsubstr.htm. James (Salty Dog)>

Alternative sand substrate Hi Mr. Fenner, I've been reading in your daily FAQs, and older FAQs from lots of people that use the Southdown play sand from Home Depot. <Yes, a dear acquaintance is quite "buff" (she) from hefting several pallets about this far to the west (California)> Unfortunately, I live in Montreal, Canada, and we do not have that brand here. Although we do have the Home Depot store chain here. <Do make inquiries... if you can get a few pet-fish friends together, perhaps a whole pallet or two can be special ordered, shipped up> They do carry the line of different types of sand of another brand that is called Quikrete. I've looked at the sands, and while they do have what they call a common blend of sand that has a warning on the label that says it contains silica in it, <It does, in high concentration> they have another blend that is labeled for sand-boxes that has been washed, cleaned, and dried, and does not say anything on the label about any silicates in it. Have you ever heard of this brand because the company is in the States? <This natural product is not consistent... you can look with a magnifying glass, low powered microscope to easily assess how much silicate/sand is present... the shinier, flatter, smoother "poker-chip" like pieces...> Would the fact that nothing is on the label for the play box type about silicates make it safe enough to use in a reef-tank, or it means nothing, and I would be better off not chancing it? <Worth investigating further. Please do post your query to our: http://talk.wetwebfotos.com/ and other bulletin board, chatforums in the hobby... some folks will certainly have recent personal experience here> I figured that if this sand is catered to sand-boxes, they would know enough not to make it health hazardous for the children that will be playing in it, since the silica is a known cancerous agent. <Umm, actually... most everything is a "cancerous agent" (in point of fact our bodies are quite cancerous... not a joke)... in quantity, type of exposure... In the grand scheme, scale of things, large particles of silicon dioxide (a very common, ubiquitous component of the surface of this planet) are relatively non-toxic> I would really like to find an alternative to buying something like the CaribSea brand because around here, the cheapest I've found for CaribSea is $32.00 for 15lbs., while the Quikrete brand for instance costs $4.95 for 50lbs. What a difference in price eh!!!! <I'll say! See my comments above...> I've also looked online at the CaribSea brand, and while it is cheaper a bit, once you add in shipping etc. it comes out to the same price. I just think it is crazy to pay that high price for sand, ( while the composition of the CaribSea brand might justify the high price, I would really prefer an alternative if it would do just as well, as this hobby is expensive enough!!). <Agreed... but not for the industrious! Bob Fenner> Thanks in advance, Greg N.

Is Pink Fiji Sand O.k. stuff? Bob, Thanks for the help lately. Much appreciated. <You're welcome> Is there any reason not to use Pink Fiji Sand in my main tank? I plan to have stars and maybe a sand sifting blenny. I forgot who it's packaged by, the packager is something like Custom Imports (they package aragonite sand also). Anyways, it's made for marine tanks, but wanted to make sure there wasn't any reason not to use it. <None I'm aware of> I already have a sump with a plenum using aragonite sand to help with buffering, but wanted something a little more fine and appealing in the main tank. I assume you have to keep an eye out not to get this stuff too deep, in case of it going anaerobic. Do you recommend a max or min depth? <Not really... but to do as you suggest... keep it stirred, an eye on it...> Thanks again. Got your book (CMA) last week, love it... <Ah, good to hear/read. Be chatting. Bob Fenner> Dan

Moving Substrate to sump, and what kind of Carib-Sea to get? Bob, Thanks for your help recently. <You're welcome> I'm adding a 20 gallon or so sump to my 38 gallon FOWLR. It will have a plenum and macro-algae. I currently have Carib-sea Geomarine crushed coral in my main tank, about 1" deep. I want to change to sand in the main tank. <Good idea> Three things: I want to use the crushed coral from the main tank as the bottom layer in the new plenum for the sump. Is this the right size crushed coral for the bottom layer, and is it o.k. to use the current crushed coral? Or is there a better bottom layer material. <Should be okay... use a plastic screen mesh (like material available for screen door replacement) on top of this layer and finer material (likely coral sand) on top...> I want to change to sand in the display tank. I'm hoping you are familiar with the different Carib-sea kinds of sand. <Yes> What is the best choice for the main tank. It won't be a deep sand bed. The choices are Carib-sea pure Caribbean Aragonite(0.18-1.2mm), Carib-sea Aragamax(0.5-1.02mm), or Carib-sea Special Grade(1-1.7mm) I would like to have a blenny or starfish in the main tank. <Myself... would go with the last (Special Grade)> Of the three Carib-Sea choices above, what is the best choice for the top layer of the plenum? <As stated> Thanks a million, you're an excellent resource, and your book should be arriving on my doorstep today courtesy of UPS. Dan <Be chatting, and taking up your time... pleasurably, my friend. Bob Fenner>

Mixing sand grains Hi Guys, <Harrow> Quick question please! I have a med sized sand (CaribSea Aragonite) <ech...> and bought additional sugar sized <woo-hoo> Is it okay to place the sugar sized over the med-size? <not recommended if your goal is denitrification (all fine for that). If not, please at least add screen between layers with course grain on the bottom> My plan is DSB about 6" deep. <excellent!> Thank you guys you're doing a mighty fine job of educating us. <thank you for saying so, good sir. Anthony>

Substrate Anthony, thanks for quick response on last question. <my pleasure, good sir> Some questions about substrates. I currently have Seaflor Aruba Puka in my 75 gallon fish only. <beautiful but not at all functional without serious water movement and activity on the substrate...speaking from experience> I was looking at switching to CaribSea special grade, but not sure if that is the best choice, would like some input. <equal size grain of whichever you choose... closer to sugar fine (oolitic) is better for denitrification. whereas coarse encourages more natural amphipods and the like> I'm planning on taking a third of the old out at a time. How long in between taking another portion of substrate out? <no hard and fast rule on this one... monitor nitrogenous elements to be sure. Intervals of weeks and not days for perspective> I was the one with the Koran and Naso and you recommended leaving my biomedia in my CPR wet/duty along with adding live rock. <yes... as a hardcore reefer (rock only) it took a lot for me to admit it...hehe. But the bio-load will be significant when these fish mature> Question is....I've seen that Seachem has a product which is a biomedia called matrix to replace the BioBale/bioballs. It is suppose to complete the nitrogen process by turning nitrates to nitrogenous gas, is this stuff good/bad your input. <no experience with it, but dubious under a good bio-load such as yours> Reason I'm asking and no surprise to you, I've been getting an increase in nitrates, even with regular water changes (B/C of wet/dry). thanks Bryan. <indeed... the more efficient the bio-filter is as the fish grow, the worse the nitrates will get...almost ironic. You can look into various denitrification filters... some DIY (coil, Deep Sand Bed, batch, etc) but water changes will always be a best bet. Consider automating the water changes. Inquire if you go this route for assistance. Best of luck to you, Anthony>

Silicate based sand Robert, I'm looking into silicate based sands for my marine FOWLR tank. The only reason is that I can fill my 80 gallon long with 3 to 4 inches of sand for $5 versus the $200 for any of the local aragonite sand. Some people say this is fine. Others say it isn't. I realize that with silicate based sands I'd get no PH buffer and I could have a problem with nuisance algae. Then again, I've also read that the algae won't be any more of a problem than with aragonite sand. I can seed the sand with GARF grunge (I live about 5 miles from GARF so that's not an issue at all) but I'm curious to know if there is any reason silicate sand wouldn't make a good live sand bed. Any thoughts? I'll probably get the aragonite anyway, but I'm just really curious. <Please read here: http://www.wetwebmedia.com/marsubstr.htm I would not use a silicate based substrate in nearly all types of marine set-ups... for the reasons you have listed above and others in the article cited. Bob Fenner> David Rencher

Re: Silicate based sand Oh, you mean I could have just read the website for the answer? DOH! How silly of me to forget. Thanks <Thank you my friend. Be chatting. Bob F>

Sand I just need a small amount of sand for the bottom of a 20gl tank. My LFS only has bags of it in 30lb. increments and it's very expensive. Is it ok to just get some sand off the beach or within the first few feet of the shoreline and really rinse it thoroughly or would it be polluted and unusable? Thank you. <Please read here: http://www.wetwebmedia.com/livesand.htm and the associated, linked FAQs. There are other companies that will sell, send you smaller amounts including just a few pounds of "safe" LS to seed your system. These are linked on our sites. Bob Fenner> Elizabeth K. Birdwell

Substrate Questions Hi again, and thanks for the excellent advise as usual! I have another question about the type of substrate to use for my new 180 gallon fish only tank. I prefer to use a very thin layer of sand grade for the substrate instead of a course coral substrate based mostly on what I was reading in the WWM FAQ's. I noticed someone stated course substrate is harder to maintain, more detritus and "bugs" can develop in the substrate. Is this true? <All three are true, the first two are disadvantages, the last part about bugs is a good thing.> I was told be someone else not to use sand for a fish only tank, not sure exactly why. <Bare bottom tanks are very easy to clean, but can be ugly.> I have a good protein skimmer, (DAS BX-1) and it appears to be working fine now on my smaller tank in keeping the nitrates down, (around 15-20p) . My intent is to keep the nitrates really low and eliminate much of the extra debris / detritus that develops on the bottom of the tank. If sand is ok, how deep should the bed be? <For good denitrification and no settled detritus, use a 4" sand bed of fine sugar size aragonite.> Any suggestions would be great! <Have a nice night. -Steven Pro>

Sand Preference I'm working on going to a deep sand bed. Quick question. If I go to 4" or so for the deep sand bed, is it better to use Carib-sea Seaflor (about 1mm) particle size, or the oolitic Aragamax (0.3-1mm)? Will the smaller grain size be too easy to disturb with high current flow flowing through the tank (12x). <Not unless directed down at the sand. I have never had a problem with it and many of the tanks I setup have flow rates approaching 20X per hour.> This is for a fish w/ LR system. Just not sure what the better substrate is. I would figure the Seaflor product since its been out longer and I've used it in the past. Not sure if the sand would be just too fine. Any insight would be appreciated. -Jim <The larger grain size tends to allow detritus to settle between the sand particles and requires regular vacuuming to keep clean. Also, I had have a terrible time getting anything to grow in it. I have inoculated it many times with various worms, many starfish, and pods and they do not do well. -Steven Pro>

Substrate Follow-up With all due respect Steve, I just want to question your advise on using the 4" substrate of aragonite in my particular setup. This is going to be a large fish only tank. I do not plan on keeping any small invertebrates or fishes used for stirring up the surface of the substrate, (in order to create the denitrifying aerobic bacteria). <You don't really need any small fish to stir your sand. Most of this can be effectively accomplished by the tiny critters that make the DSB their home; bristleworms, Chitons, amphipods, copepods, spaghetti worms, etc. I merely mentioned the DSB possibility because you referred to eliminating nitrates in your question about substrate options. I thought that was where you were going.> Shouldn't I just use a very thin layer of aragonite to avoid any problems? <A thin layer will be fine. -Steven Pro>

The Opinion of Aquatic Experts Hello WWM Crew, I have a couple of questions. Is it true that you should not have a big bed of aragonite? I have 270 lbs of Aragonite in my 180 gallon tank and have been told by 2 different people that I should remove it and replace it with crushed coral since the Aragonite will turn into a mush and retain all sorts of nasty things. <Definitely not what I would do. I prefer to use a deep sand bed, 4" or more of fine aragonite sand.> The other thing they said is that I should not run the skimmer 24 X 7 that I should only run it a couple times a week or that otherwise the LR won't get the nutrients that it needs, this was told to me by two supposedly "Aquatic Experts". Is this true or are they just out of their minds? <I strongly disagree on both counts. Do not just blindly follow my opinion or recommendations. Get the advise of others. Read books, magazines, and online chat forums to formulate your own educated opinion.> Once again thanks. <You are welcome. -Steven Pro>

Silica in my puffer tank Hi ..I have a new Tank (4 weeks after maturing) and I have 3 puffers in there...before I knew any different I used tap water and that has resulted in horrible brown water ..I have since moved on to RO water .. although reassures it will not hurt my cherished puffers I wondered if there was anything we can do top speed up the process of getting rid of the silica ..we have a poly filter and have put carbon into the filter .. thanks a lot Steve <Mmm, there are a few things... some chemical filtrants, using other organisms to take up the silicate... but I would just wait... time and regular maintenance will resolve/solve this issue best. Bob Fenner>

Substrate question Fond greetings to all of you at WWM <and kind regards to you my friend> Sincerely hope everyone had a great holiday with good food, good drink and most of all family and friends. <and you as well <smile>. In fact, we haven't stopped... Steve and I out to sunny California to visit our good friend Bob. A great feast and fellowship planned for tonight> Anthony, thank you for your very prompt reply several days ago regarding my question on a used protein skimmer. I've decided to opt for an AquaC EV 180, rated for tanks up to 150 gallons. <outstanding... you will not be disappointed> Now, I have a question about substrates. I did a search on the WWM site looking for the answer but couldn't find exactly what I wanted. In one of the articles about setting up a marine reef tank, Mr. Fenner wrote, "Calcite with magnesium impurities. Coral sand, crushed oyster and coral rock. These are the most suitable media and buffers. Size (2-5mm), shape (spherical), grading (all the same), and circulation (2+ gsfm, the more the merrier) have been gone over under properties." My question: Is Mr. Fenner saying one can use coral sand OR crushed oyster and coral rock OR a combination of all three. Could I mix up all 3 types to use as a substrate? <not recommended... each/some have advantages over others. All are calcium carbonate... some calcite (crushed coral, shell)...some aragonite (best IMO for buffering)> Actually, if you can, I'd appreciate you telling me if there is a particular brand name <no brand recommendation... all aragonite in the country is collected by one company and repackaged. Just buy the cheapest. Fine aragonite sand from Home Depot (South Down brand) is quite popular> that you recommend that I can tell my LFS person to get in case he doesn't already have it on hand. I looked around on the internet, but a lot of places don't tell you the properties of the substrates they sell. I did look at Custom Aquatic, Kent Marine (their Biosediment looks like it might fit the bill), Eco System's Miracle Mud, <I'm not impressed with the latter two regarding value for price paid. You literally need to be paying mere tens of cents per pound> and Kordon Aquarium. Problem is, I just don't know which one to choose. The tank I'm setting up will be a 140 gallon with no UG filter (unless that's necessary); the AquaC skimmer, Tidepool 2, a Mag Drive 7 and Mag Drive 5 and JBJ lights. I plan on adding 75 to 100 lbs. of live rock or more if needed and, after 4 to 6 weeks (if all goes well), I'll begin adding some live corals (but no SPS corals or clams as you cautioned against that due to the lighting). <and do be sure to hold off on putting any coral or livestock in until most all live rock is in. Any added later must be cured at home (never trust any shipped rock to be cured)> Then I'll introduce (after dipping/QT) 1 to 2 fish a month, some scavengers, cleaners, etc. Many thanks for the awesome site and the equally awesome advice! Diane (down in the Louisiana bayous and still eagerly waiting for delivery of the CMA book) <best regards, Anthony>

Oyster shell filtration 7/4/05 Dear crew, Thanks for all the useful information on your site. I have started a new 46 gallon saltwater tank that has been up for 4 months. I have 2x65 pc lighting which I am going to upgrade soon. In the beginning I had 1/2 bio balls and 1/2 coral shells in my sump with live sand and macro algae. I recently bought some oysters to eat and came up with the Idea of using the shells upside down in my sump. I double boiled them and cleaned them and began to place them upside down in my sump, using live sand in the cup of the shell. It is a big guess of course but the way the water flowed from the wavy tips of the shell into the belly of the next seemed that it would work really well. And it only took me out about 4 bucks for the shells and a meal. But now I only seem to be growing the hard green algae. I would like to have a little more of the kind a purple tang could eat, as I am going to get one when I feel my tank is ready. The rest of my set up is (1 false perc and seabae,1 coral beauty, 1 mandarin, 1 diamond watchman goby, 10 snails, 6 hermits 30 pounds of live rock and a 200.00 skimmer.) I am also using the sump inlet area as a sort of staging area for Caulerpa and copepods I have purchased for my mandarin. Any advice? <... have used Oyster shells... fresh and processed (mainly for chicken supplement)... not very soluble useful compounds for saltwater... Coverage on how to grow purposeful macroalgae and the fish you list above is archived on WWM. Bob Fenner>

Rubble Rock 8/2/05 I am in the final stages of setting up my 180 gallon FOWLR tank and saw rubble rock at a local aquarium store. I was thinking this would possibly be good to put in a refugium, What are your thoughts. If you feel it a good idea can you give me recommendations on how thick the layer should be, lighting, circulation, etc. - DWayne <Hi D'Wayne! Thanks for your inquiry, regarding the rubble rock - it would be just fine to use in your refugium. Keeping a fine grain 3-6" sandbed in the fuge and/or several pounds of rubble live rock is all you need. Depending on your set-up goals, lighting can be used or deleted from the set-up all together. Please feel free to do a search regarding refugium set-ups here. Tons of info, you'll be pleased D'Wayne... - Ali>

Substrate particle size Hi again, Well this is kinda off subject, but the sand I have in my tanks now is aragonite which is about 2-3mm in size. I have read in a variety of places its better to have sugar size sand (oolite?), so animals can burrow into it. I have also heard that there is a sand that hardware/home stores sell that can be used in the tank, which I'm sure is cheaper than buying it at the LFS. Have you heard of such a sand, and if so what is it called :). Thanks. Chris >> Hmm, I'd like to know what this sand is... at the hardware store... Most all I've ever seen are silicates (kiddie play box sand), metamorphic chondrites ("gravel" for freshwater), and maybe flints (good for some freshwater systems)... maybe dolomitious material or Tapashell (mainly calcium and magnesium carbonates) you could find at such outlets that were in "farming" areas... And, nah to the finer substrates (oolithic... fine, dusty stuff)... as being better... they have their own sets of problems. You're better off with the 2-3mm stuff of all about the same grade... Maybe place the sugar stuff in a refugium... Bob Fenner

Play sand... This is the question I am commenting on. This sand that the person is talking about is a tropical play sand packaged by Southdown, the same company that packages for CaribSea. It is the exact same stuff. It is found at Home Depot for less than $4.00 for a 50 lb. bag. Compared to $1.00 a lb. from CaribSea. Let me know if you want any more info on this. I know plenty of people that have it in their tank and it works and looks great. (it should, it is the same stuff meant for aquariums) I have a few bags on order. Ryan QUESTION: Well this is kinda off subject, but the sand I have in my tanks now is aragonite which is about 2-3mm in size. I have read in a variety of places its better to have sugar size sand (oolite?), so animals can burrow into it. I have also heard that there is a sand that hardware stores sell that can be used in the tank, which I'm sure is cheaper than buying it at the LFS. Have you heard of such a sand, and if so what is it called :). Bob's Answer: Hmm, I'd like to know what this sand is at the hardware store. Most all I've ever seen are silicates (kiddie play box sand), metamorphic chondrites ("gravel" for freshwater), and maybe flints (good for some freshwater systems). None of these are good for marine aquariums. And, nah to the finer substrates (oolithic... fine, dusty stuff) as being better. They have their own sets of problems. You're better off with the 2-3mm stuff of all about the same grade. Maybe place the sugar stuff in a refugium. >> Am sort of aware of the sand... but still a little leery of posting much about it... but will indeed send this info. to FFExpress and the original querier... Do you screen it at all? Ever find much/any contaminants... Probably not... as it's intended for "kiddies"... Bob "the worry wart, but a real cheapskate as well" Fenner

Sand does silica sand work as a good substrate . it is available in different sizes. it is used in sandblasting operations a lot .thanks. Jim bell >> For some applications in fresh, brackish and marine set-ups, but not many... Silica is too smooth (too little surface area for bacterial situating), chemically inert (it's aka silicon dioxide, the chief ingredient in glass... you want something to contribute to alkaline reserve: carbonate based), too flat (packing down, disallowing water flow, encouraging anaerobiosis)... Take a look at the Marine Substrates piece stored at my site: www.wetwebmedia.com for a more complete survey of the yes/no question of whether to use substrate, the various types of use, and their pros/cons... Bob Fenner

Re: anemone I guess aragonite is too coarse? I just read your message again. >> <Aragonite is a generic term... in disuse... referring to any easily soluble calcium carbonaceous material... if it is fine enough, no problem... something more than 30 pieces per linear inch (sand) is what I'm referring to... Bob Fenner

58 Setup Question Bob, After having read all of your comments about live rock/sand I am convinced that this is the way to go. In the past I have only kept fish-only tanks with no live rock/sand. For this reason, I am woefully ignorant about how to go about setting up a tank with live rock. It sounds like Fiji rock would be the way to go. How much Fiji rock would I need for an Oceanic 58 reef ready setup? <Of Fiji or other rock, functionally, somewhere between one and two or so pounds per gallon volume of the system... Look for "box" deals, and more "ready-cured" product> Would you recommend that I purchase the live sand at the same time? <No. I would rely largely on "making your own" through inoculation incidental with adding the live rock... you understand> How much live sand would I need? <Of appropriate grade, more spherical calcium carbonate based material, about the same rate as the live rock... depending on whether you intend to install/maintenance a plenum in your main tank... Take a read through the Marine Index... marine substrates materials stored on the site: Home Page for a more thorough input> How in the world do you keep it clean? <Periodic vacuuming, stirring in conjunction with water changes, AND use of purposeful "sand stirrers" in the way of livestock, AND adequate circulation and filtration, AND periodic (every six months or so) augmentation, replacement of the mineral matrix> I assume that I don't want to vacuum clean it like I do with crushed coral in a fish only tank. What would you think about purchasing some really porous base rock to fill the tank about half way and then put the Fiji rock on top to seed it? <Something like this is feasible, advisable... I prefer to let the rock sit on the bottom or a raised grid, and corral the live sand around this area IF PLACING THE LS IN THE SYSTEM. I vastly prefer re-locating live sand, plenums... in a separate sump outside the main/display system to facilitate maintenance, growth of beneficial life in the absence of predators, competitors...> Where could I find this kind of base rock? I've heard that some use lava rock--is this recommended? <No to lava rock, other siliceous rock types in the vast majority of marine systems... this volcanic/silica-based material is of little use for its lack of surface area (at the molecular, practical levels), introduction of silicon (a primary source of diatom algal growth boosting), and lack of contribution of biomineral and alkaline reserve input> What kind of lighting would you recommend? The 58 setup comes with a twin strip. I'm thinking some 50/50s and then purchase some VHOs or something like that. What do you think? <Depends on what you want to keep and what you want to do with "it"...Take a long read through the site above's materials on light, lighting, and set-up> I'm also ignorant of the alkalinity, calcium, dosers and all that is associated with reef fish keeping. What do I need and where can I get it? <Time for some reference works my friend... these are good questions, but way too much to cover as a "reef-friend" in this communication format... Get thee to some like-minded friends in a local hobby group... at least one "reefer" who can/will take you under their wing... to one on one cover these important issues... and Read! as much printed matter in the field as you can get your fins on> I believe that the liverock would be sufficient for filtration. My plan is to hook up some kind of needle-driven protein skimmer in the sump and some means for chemical filtration (Chemi-pure/PolyFilter). Would you recommend this? <Yes, periodic use... once a month or so...> If so, how do I go about setting this up? <See the site> It seems like if you want to buy something to go under the tank you end up getting a wet/dry with it (and I take it that I don't want to do this unless I want a lot of nitrates). If I purchase just a tank as a sump then chemical filtration becomes difficult. What should I do? <Ditto> I really want to do this right. I don't want to skimp on the quality of my purchases and have to upgrade later because I wasn't willing to take the extra effort to maintain a reef setup properly. I guess what I am asking is for you to tell me exactly what you would do if you had my 58 and wanted the perfect reef set up--rock, sand, lights, filtration, dosers, tests, etc. What are the names of the dealers out there that you recommend that sell the rock/sand, filters, lights, etc. that I need (who have you found provides quality merchandise?)? <Lots of folks, but hear me out... It is impractical to try and elucidate what my or others opinions are on how to "strictly go ahead" with a 58 gallon system w/o knowing what you want to keep, and what your goals are (maintenance, growth, color, reproduction, commercial....)> I know that this is a lot to ask but I really value your opinion--at this point I plan on purchasing the equipment/items from the manufacturers/dealers you recommend. Thanks for all of your help! Michael Krogman >> <Keep investigating, reading, taking notes, dreaming and scheming my friend. The anticipation of this endeavor is a great deal of the fun and learning which is the hobby/experience. Bob Fenner>

Substrate Question Hello Robert, I'm am new to the hobby and I have been reading your site religiously everyday. Good job and keep up the good work. <Hope to, thanks> I have a couple of quick questions. I used magnets to clean algae on my tank (55gal.). Once in a while, the inside part of the magnet falls down to the substrate. When I pick it up, I notice that there are little metal fragments attached to the magnet. My question is simple, is this bad or good? Should I replace it as soon as possible? <Not good... evidence of some sort of ferrous material in your system/substrate... good to tie a string sort of arrangement to the inner magnet (to retrieve it in general) and "fish about" for as much of this material and remove it... in time most such foreign matter tends to become less toxic... coated over in ways... but best to avoid its introduction, and better to try and remove as I've stated> Thanks in advance. Sincerely, Aldrin <Be seeing you, Bob Fenner>

Re: Substrate Question Thanks for the quick response. I was jumping up and down in excitement when I actually received an answer from you. You are the man! <The petfish man!> A local fish store here sells a sugar-size aragonite. Do you recommend this, or should I go with bigger size grains? <For some applications yes... but not for a general tank bottom> Which type of substrate would you recommend if not aragonite? <For most types of tanks something calcareous... Hey, I should be sending you to the "marine substrate" section of the site: www.WetWebMedia.com under the marine index... wrote, stored my ideas on the topic during some few lucid moments... let me know what you think of the site> Thanks again. Sincerely, Aldrin <Be chatting, Bob Fenner>

Substrates for marine systems Lorenzo, <Hi Thom.> I have been reading and gathering my toys to set up a 40g tank. I read about the use of Home Depot's Southland sand for the substrate. It's attraction is that it is very inexpensive (some would say cheap). Is this the tip of a new trend/product? Is this really safe to use? I am thinking of a 50/50 mix with fine aragonite about 2" deep. I would appreciate your opinions about this. <I personally haven't tried it, but I too have head stories of it's success. Still, in my opinion, a 40 gallon tank shouldn't clean you out, trying to build a 2" sand bed from known-good aragonite... -Lorenzo> You must be a great friend to stay home and do "Bob's work" while he is in Asia doing the fun and sun thing. <<He is. Bob F.>> <Hah! Well, yeah. Bob's a good guy, and I'm excited to see what new photos he brings back...!> Thanks for your input. Thom Walters

Substrate for marine system Hello Robert, <Hello> Once again I would like to commend you and Wet-Web-Media. I also would like to thank Lorenzo, who performed an admiral job in your absence (he's closing in on you Bob). <He's way beyond yours truly> Well, I am finally closing in on the home stretch with my 75G reef and wanted your advise on substrate. I have decided to go with substrate (in the tank, no holes) but which one? I have narrowed it down to two: Nature's Ocean Bio-boosted Aragonite and the Fiji live sand. Which would you consider for your environment. <Both... mostly the former, with ten pounds or so of the latter sprinkled on top> Additionally, should I place the sand and use 2-3" PVC to elevate the 110+ lbs of rock (for the stirring critters and cleaning) or place the rock on the bare bottom and position the sand around it. Are there any benefits either way? <Benefits of both in terms of cleaning, stability physically... I would place the material directly on the bottom, sand after.> One other side-note, I purchased the Marine Environment Salt Mix and am having a devil of a time getting it to clear, I am able to get the proper salinity. I stirred the mix thoroughly in a bucket and there is just a small amount of salt grains in the bottom of the tank. The mixed water (RO water) has been in the tank for 5+ days and still has not cleared, <It will... do just place this water in your main tank> additionally there appeared a dusting of salt on the glass and power-heads (which I removed with a squeegee) but it re-settled on the power-heads. Currently I do not have any animals in the tank (only power-heads). I am seeking help as I have not used this product before but understand it is supposed to be superior. <It's a good "regular" product> Other products I have used have not taken this long to clear. Is there something I am doing wrong? Or is the wait period much longer for this product, should I get a hang-on or canister filter to assist in clearing? <Instant, complete dissolution of ME is not one of its strong, consistent points... as I stated, just place it and it will clear, dissolve the remaining components over time> I discussed this with the manufacturer and they stated it's anything but the mix (i.e. my water or my mixing container is contaminated) <Not IMO/E.> Fred, in hot Las Vegas (I think I'm gonna need a chiller) <Hmm. I suspect your living space is already air-conditioned... wait off and see how warm your water gets. Bob Fenner>

Curing LR/lighting, marine substrate on the cheap Hi Bob, Hope you had a good weekend. <Yes my friend. Thank you. Hope yours was as well> As for your question regarding the beer, I guess that's why the came up with the slogan, "Why ask why..." :-) <oh yes> Well, as always, answers bring rise to new questions. <If they're good ones> Here's today's questions: with a new tank setup, I would really prefer to re-cure all 90lbs of LR in place in one shot. What are cons of doing it this way, versus curing two 45lb batches as you recommended? <Really, only the added possibility/chance of "overwhelming" the system and its mechanicals... and having too much, too soon of the live part of the rock die off... Always a chance of this... but smaller batches... mixed with already cured LR... less potential> Also, I've seen various posts regarding the Southdown sand at Home Depot. Have you had anymore experience with that? <Yes, ugh, mainly lifting bags...> In your latest responses on that subject, it didn't seem that you really had an opinion regarding its use. I'm mainly interested in the buffering capacity of the sand, (similar to coral sand?) <Hmm, almost identical... does have equivalent properties, composition... should look through, possibly screen for misc. glass and metal pieces... though I've never encountered any.> ... and the cheap price of course! Thanks again. <It is indeed a real bargain. Bob Fenner>

Marine substrate Good morning Bob, Hope you had a fun/safe 4th. <Yes, stayed home "working"...> I almost hate to keep bringing up this same subject, but I've checked a few message boards and couldn't find an answer, (wish the WetWeb forum was up). <Soon my friend> It's about use of the Southdown play sand as substrate again. I've been to several Home Depots looking for this stuff, but all of them carried the brand, Paragon, instead of Southdown. I was wondering if you had any experience with this Paragon brand, and knew if it was the same/similar stuff. <Hmm, don't know... do remember being told of the Southdown not generally being shipped too far away from the source (Florida) due to economics... but also know of folks who with perseverance have bought a few pallet loads and had it delivered all the way to California... maybe a few phone calls, gathering like-minded folks together (hobbyists in a club? Local retailers?) for a semi-huge order? Bob Fenner> Again, sorry to keep coming back to this same subject. Thanks as always.

Hard time with (substrate choices for marines) Hello Bob, I am reading lots of your material, but this time I have a friend that is in the medical field and knows the different values and chemistry. I am starting to make more sense of the chemical balance. <Sounds good> I am also trying to take control of the green hair algae and green algae that covers my glass daily. I have added some Cerith and some Nassarius snails. My question is: I used Seaflor Aragonite Reef Sand, which is rather course. Is this a "fine" enough sand bed for the Nassarius or should I add some find grain sand to the bed? <Finer would be better for them. Bob Fenner> Thank, Dave

Crushed Oyster Shell as Substrate? Dear Mr. Fenner, I have been maintaining a F/O 30 gal salt tank for about 2 yrs. NEVER a reef tank. I am trying to set up a 125 gal reef as inexpensively as possible without downgrading quality. So I am researching each and every purchase thoroughly before deciding. I am up to "substrate" at this point. <Okay> I am in the Midwest, thus sand/live sand is hard for me to get (without driving 150 miles) AND BOY! shipping for 200 lbs is crazy! My ONLY local fish store is "PETCO", big choices there! ;) I have also looked for the famous "Southdown" sand here and it's just not gonna happen without eBay prices and shipping. <Hmm, how about the Home Depot sand alternative? Please consult/consort (!) with our Chatforum (www.WetWebMedia.com is the homepage, link there... am on the road, can't cut/paste) re its availability in your area> I am also currently creating cement rocks with crushed oyster shell, something that I have PLENTY of in the Midwest ;). My question is, Could I possibly use the "crushed oyster shell" as a substrate? <Hmm, well, can... please see the "Marine Substrates" section on our site (WWM) here> I have been searching forums and sites about this and have read about 50 "absolutely nots" and about 2 "I use nothing else". What do you think? <Possible, generally not advised... that is, typically, substrates are a plus> My uneducated theory is that if it's ok in the rocks, why wouldn't it be ok for the substrate? If you think it is possible, Could you recommend how deep? For a 30 gal hex & 125 gal? <Again, pls see the "complete answer" article on our site here> I'm sure you get a ton of letters, emails daily, and I thank you for your time and consideration! <have been out at the MACNA XIII hobby conference the last few days... sorry for the delay in response> Amy Horn P.S. I have ordered your "The Conscientious Marine Aquarist". I am patiently awaiting its arrival to my local book store. 1 week down, 1 week to go ! <You will not be disappointed my friend. A note of sorry in advance... for the hours we will share together in your reading of this work. Bob Fenner>

Sand bed Hi, Bob and good evening. I'm still confused about this sand bed and live sand. Somebody on the net tells me now that the live sand my dealer sells has only bacteria in it, but none of the important "critters" that I need to get the sand sifted. <This is possible. There are such products.> They suggest that I put 3" of sand collected on our beach on the bottom. Then 2 bags of the live sand from the store and on top of it 1" real live sand from our beach collected in 3' of water. That would give me all the critters. <A dangerous proposition... pests, parasites, pollution too likely present. I would just use some live rock with whatever source of substrate... the LR will inoculate it fine> Can any phosphate in the sand be filtered out later? <Mmm, yes... or bio-accumulated.> I might find a stretch of more or less clean beach not too far away, but we still have rivers and the city polluting the ocean. I find a lot of 'sand dollars' close to the beach in the ocean. Is that a sign of good water? <Not necessarily> Can those animals live in a tank. <Yes. There are public displays of these echinoderms about. And many labs utilize Sand Dollars for research...> I never read anything about them. They bury in the sand. Why the big difference in the depth of a sand bed. Will a 1.5" bed not work biologically? <Depending on depth, chemical make-up, angularity, s/b fine. Please start reading here: http://wetwebmedia.com/marsubstr.htm and here: http://wetwebmedia.com/livesand.htm> Now that I have solved my problem with the temperature, I have another one. I had 2x20 W and 1x15W bulbs on my tank, but now I can fit only 2 x 20 W light fixtures on the remaining glass covers. The rest is open for ventilation. Will 2 x 10 000 K bulbs be enough for the FO tank? <Yes. Bob Fenner> Thanks, Bernd

Re: Sand bed Hi, Bob. Thanks again for Your well appreciated help. I now have enough new stuff to read. Good night. Bernd <Chat with you soon my friend. Bob Fenner>

Set Up and using local ingredients Aloha! <Salutem dicit my Hawaiian friend> Sorry if my question is a dumb one but, I am about to set up a 50 gal Marine tank. I plan on purchasing a protein skimmer or a combination bio. skimmer like Bak 2 . If this sounds like it will work fine. But, my main question is, I live 50 ft from the ocean here in Kauai. I would like to use the local sand and rock <Mmm, not to be perceived as too Spartan, but don't get caught... a no-no in HI with the DNR> instead of buying live rock and sand. I will probably use fish I order and some local varieties as well. Can or should I use the local sand and rock or still order it from somewhere else? <Ah, I would very likely use the materials at your immediate disposal... If in doubt at all, let the collected substrate run w/o other livestock till you register appreciable nitrate, no ammonia, nitrite... Bob Fenner> Mahalo for your response <You're welcome>

Marine fish Hi, Bob. Can you tell me good web site that shows pictures of marine fish including a short description of them (length, adaptability, etc). <Wish I could... I use Scott Michael's Pocket Guide and Reef Fishes books, the old WEB/HRA/RayH TFH Atlas... and a bunch of other references... oh, including fishbase.org on the Net...> I just love Your web sites. If I put 1" coral gravel in the tank that is big enough in size to be washed with a gravel cleaner without being sucked up, what size would You recommend by No.? <Five> I found web sites that sell gravel sized by No. From 2-20. I see that anything above 10 is too large but between 2, 3, 5, I can't distinguish the size of the pebbles. I have to tell my dealer the size by No. so that he can order it. Thanks, Bernd

Re: Marine fish Hi, Bob. Thank You for Your great advice as usual. Bernd <A pleasure my friend. Bob Fenner>

Sand (for marine substrate) Hi, Bob and good day. Thanks for Your advice on magazines. I looked on some of their web sites. Not bad. When I went through my 100+ old TFH magazines I came across a lot of Your articles which I'm reading about a zillion times now. My freshwater tank is gone and the aquarium is clean and ready to be set up as a marine fish tank. I received 3 bags (about 150 lbs) very fine ,less then 1 mm diameter, coral sand from a friend of mine who owns a key island on Guanaja. Very clean 'off white' sand. I will wash it and then put about 1" on the bottom of my tank. Is that o.k.? <Yes, likely fine> My petstore here has no sand whatsoever at the moment, so I'm stuck with what I have anyway. Then I will put the coral decoration in and then I have to wait for the salt, test kit and equipment that I ordered ( bio wheel to go with my canister filter, 2 power heads). I will keep You updated. Regards, Bernd <Be chatting my friend. Bob Fenner>

Filter Media Question I have a gravity flow sand filter that I built myself. I use a blower to stir the material for cleaning. <Neat> I am looking for some choices in filter media that will work like sand, but are lighter in weight to improve my cleaning process. <Hmm, there are media of different densities...> Do you carry any such materials? Can you direct me to a source if you don't? <I/we don't offer such products... would check with your LFS re "special ordering" such from their dealers... maybe mention Tideline in L.A.... and look around, see what other hobbyists are using... maybe devise a "test bench" for gauging density... The Home Depot sand, various Aragonitic sources, dolomitious materials... many choices to test, use. Perhaps peruse this part of our site: http://wetwebmedia.com/marsubstr.htm and the links, FAQs beyond. Good hunting. Bob Fenner> Thank you.

Looking for a Cheap Sand Source Bob, <<JasonC here filling in while Bob is away diving.>> I'm looking for some "home-depot" cheapo sand to mix with my 30lb of live sand and live rock, I've heard that play-sand and blasting-sand have silica and are to be avoided. <<this is true>> so if you could steer my in the right direction, me and my wallet would be thankful. <<Keep your eyes peeled for the brand "Southdown" This is probably best suited for the base of deep sand beds and refugiums as it is very fine BUT... it is re-branded stuff from CaribSea [or so the rumor goes] and so Southdown is supposed to be pure aragonite. This is about the only thing at a Home Depot that I could recommend for use in a fish tank.>> thanks and happy holidays <<You are welcome, and yourself as well. Cheers, J -- >>

Re: New tank setting it up (marine substrates) Hi Bob and JasonC, How was the dive? How about posting some pics? <Fine... and we do... daily> hehe.. Well I got my tank filled with saltwater from the Waikiki Aquarium for about a week now. It's a pretty good deal, you pay a one year membership, you get saltwater for free from their well which is naturally filtered, free entrance anytime they're open, and invitations to their special events. I think now is the time to put some substrate in and base rock. I was at the Home Depot looking for the infamous Southdown to no avail but they do have a 60 pound bag of sand for $2.68. Its a local product labeled "Coral", it looks pretty fine like aragonite. The LFS in my area sells aragonite for $10 per 10 pound bag. I am at an impasse here on which one to use. <Chat with other aquarists there... test some of the inexpensive product...> The aragonite at the LFS is a little bit more finer than the coral but is more expensive. I read that coral is not really good as a substrate (something to do with nitrates?) and fine aragonite on the other hand has a problem of cementing the surface? <Both of these are "possible" shortcomings... there is huge variability in these products> I need some advice. I have read that if I am going to use fine substrate such as these, I should not lay it on too thick while other sites I've read are saying the exact opposite and saying that I should use up to 4 inches! What do you think? As always thank you for your help and Happy Holidays!.. <Please read here: http://www.wetwebmedia.com/marsubstr.htm and where the links lead you. Bob Fenner> Sand Bed Hello Mr. Fenner, I want to say right off the bat how thankful I am for your book and web site. <Thank you my friend. Getting better all the time> A year ago I bought a 75 gallon aquarium to keep marine fish. "It's not any harder the FW, just more expensive." Geez I had no clue. Mixing salt to the water then to the tank, feeding only flake food, the same gravel as my FW tank (I'm sure you know all of the bad stories of people who started the same as I.) <New ones most days> I am ashamed of my ignorance towards this hobby and how lazy I was about fixing it. <Ah! But aware of where you were, going elsewhere/forward> After too long I am now hell bent on going it the right way and have formed a good plan. I bought 85lbs of LR. A skimmer!! I am learning about different food stuffs and everyday maintenance. I ordered power compact lighting last week and I have a refugium empty and waiting to be filled. :) Very excited. <Yes!> My next upgrade will be adding a 4" sand bed. What I have right now is (1 1/2") live sand & crushed coral mix that looks to be active. Worms and clams and creatures that I have no idea who they are moving around in it. I will also add a 4" sand bed to my refugium. <Good> This brings me to my question. I live in Fort Bragg in Northern California. I am right on the beach as a matter of fact (lucky me.) I am wondering since I do not need live sand, I am assuming my active bed will seed whatever I put in it (Slowly of course) would it be acceptable to go down in the waves and get some of our sand (beach ranger permitting)? <Not a good idea actually... too much/cold difference in temperature for the majority of organisms to bridge... Along with concerns re pollution, pests...> From 55* to my tank that is at 80*. I am sure all of the critters will die off (will sieve it to take out larger stuff) but I wonder if it will do the same as sand from my nearest marine store. I don't think it will harm anything, I guess the best question is will it do any good for it? <Not really... well, perhaps as an experiment... but not in/with your main tank. You will/would suffer "cloudy water" problems that would be persistent... from die-off, adjustment in many ways.> I am planning on increasing my water circulation. I want to get an external pump and have a spray bar (I hope that is the correct term) along the back of the tank. I am not so happy with looking at internal powerheads. :) I am wondering if you have any thoughts about going through the plumbing hell (not my strong suit) to have this setup. Do you think it would be worth it for my system? I want to have a fish and hardy invertebrates system. Perhaps a reef is the very distant future. <Lots of ideas on plumbing are posted on WWM and on to a link to Oz's Reef... a good idea to draw out/diagrammatize your various choices... to show others, gain clarity in your final design> Thank you for your time and I hope you will be able to write back. Ann <Be chatting. Bob Fenner>

Substrate and Bioballs 8/19/05 Hi, I have a few questions. First, I've read on your site that crushed marble is not a good choice as a substrate, what is the actual difference between marble and crushed coral that makes marble a bad choice? <Well, to be very general, crushed coral tends to dissolve easier in the higher ph of a marine tank, and provides some buffering and dissolved mineral content. Marble tends to dissolve much slower.> And does that matter if I'm only using the marble as a one inch substrate for looks only? <You could, but both of these materials are generally found in very coarse grades, and coarse substrates require a great deal of attention, even at shallow depths, as they will tend to trap detritus. Accumulated detritus can lower water quality and lead to outbreaks of nuisance algae. If you are intending to maintain a sandbed of any depth, I'd tend to prefer a very fine substrate, like the oolithic aragonite materials in the "sugar fine" grades.> Also, I'm changing the main filtration on my tank from a penguin BioWheel with ceramic noodles to a sump with bioballs. Most of the advice on your site says to use live rock and a deep sand bed instead of bioballs because of the nitrate factor. But I don't have room for a deep sand bed, and as far as I know the penguin/noodle combo produces lots of nitrates too but I was able to keep my nitrates at zero by using a Zeolite (I think) type medium that has the right size pores for anaerobic bacteria to live in. By my thinking, if I was controlling the nitrates before then switching to bioballs shouldn't make a big difference - is that right? <Well, bioballs offer a huge surface area for bacteria to colonize on. Possibly even more surface area than the ceramic noodles. Either material is excellent at reducing ammonia and nitrite, but both become "victims of their own success", removing ammonia and nitrite, while accumulating nitrate. Perhaps you could utilize a deep sand bed in your sump. Or, you may want to experiment with a very good protein skimmer and your aforementioned shallow sand bed in the display. Many aquarists are successfully forgoing sand beds altogether. More than one way to run a system out there...> Finally, as I said I'm going to take out the BioWheel so I was planning on running the BioWheel and bioballs together for a few months before taking out the wheel. Given that the it has been the main filtration for two years or so, do you think taking out the BioWheel suddenly will cause a problem? <May not cause a problem, but the phasing out of a very efficient biofilter for a new one is always potentially tricky. Be sure to phase out the old system slowly, and monitor water quality along the way.> Thanks for your help. <My pleasure. Regards, Scott F.> Which Sand? - 08/13/05 Hello Again, <<Greetings>> Your site has been the best thing for the hobbies since glass aquariums! <<Thank you>> My question: I will need aprox. 300LBS of sand for a 5" base, I wanted to put down the first few inches with Home Depot sand to save money, and then top off with live sand. I cant find Sanddown <<Southdown?>> name by me. But I have found "silica free" sand. Is this ok? Thank-you in Advance as Always. Dan P <<Should be fine, silica-free or otherwise. I have done this very thing with the refugium on my frag system. EricR>>