CircMarFAQ6

FAQs about Circulation in Marine Systems 6

Dissolved oxygen and waste removal...

- Too Much Turnover? - Bob, <JasonC here in his stead...> I am having a slight problem with a recent ocellaris clownfish I just purchased, he seem to have a difficult time swimming in my tank with the current. Do I have too much turnover? This is what I have as of now: 2 maxi 900s - 230 gph = 460gph 1 penguin bio wheel = 330gph for a total of 790gph. I have a 46g bow front with 50# of Fiji live rock. that is a turnover of right around 17.1x an hour. but my major questions are will the clown be ok? looks like he is struggling at times. <Some of that is just due to the way they swim... seem to be struggling but in fact they are not.> great color to him, he is eating. Will I be ok if I turn my BioWheel off until I get my skimmer? <Uhh... I wouldn't, think this does provide some of your biological filtration... would leave it running.> When I get my skimmer I plan on taking the BioWheel off the tank anyways. will my live rock be enough filtration for now until I get my skimmer? <Perhaps, but not something that I like to see happen suddenly... perhaps take the wheel itself out and let sit submerged inside the tank somewhere in case you need to get it running again soon.> thanks Tim <Cheers, J -- >

- Circulation Question - Hi Folks: Thanks for all the great info on your site. I'm new to the hobby and have been voraciously reading your words of wisdom. I have a 58 gallon FOWLR that is 8 weeks old, filled with 50lbs of live rock and 4 fish (2 YT Damsels, 1 Clown, and 1 Yellow Tang). I have a 20 gallon refugium underneath with a Mag 2 pumping 125gps back into the tank (when factoring in the height.) This week 2 fish died with what looked like tail rot and I'm concerned that a purplish algae growing on the rocks and sand is Cyanobacteria. I've been feeding with a pinch of flakes in the morning and 1 cube of frozen food at night, but have now backed off to 1/2 cube at night. After reading your many articles on circulation, I've realized that my circulation is woefully inadequate and may be the source of my problem, so I added a Maxi-jet 1200, pumping 295gph. I am also considering changing my refugium pump to a Mag 7 as advised by my LFS, which would pump 480gph at the given height. <Hmm... or just some more circulation in the tank... would allow the refugium to stay more of a refuge than a sump if you left the pump you had. You could easily get two more of those MaxiJets in there.> I am concerned that I am overdoing it on the circulation. <Nah...> Since I added the Maxi-jet, the fish are now hiding in rocks and caves and only come out at feeding time. <Could be for other reasons, but give them some time... I think you will see the fish actually like it. Am circulating roughly 1800 GPH in my 55 not including the return... should be no big deal.> Should I replace the 1200 with a lower powered model, or is this just normal behavior where the fish just need time to get used to the increased circulation? <It's a bit of a surprise at first, I think... but they should adapt to it pretty quickly.> Thanks, Ken <Cheers, J -- >

Circulation for a refugium, main tank - 3/3/04 I really appreciate your answers to my lighting questions a month ago. <No worries.> I finally received my CSL 2 x 40 PC. <Cool> The lighting is great but the fan is rather loud. <Lots of air being pushed through> If you have a couple minutes I have would appreciate your input on my plans. <Let's see what you got> Right now I have a 15 gal tall running that was an old reef but I had a mishap. This tank has about 25 lbs of LR, a Lawnmower Blenny, A Sally Lightfoot Crab, serpent star, brittle star, at least 27 small stars, a few hermits and Astrea snails. The substrate is 3'' of crushed coral. <Wow, crushed coral can be problematic. Also, it should be roughly four inches or greater> My plan is to move that tank underneath a new 10 gal and use it as a refugium. <Definitely want the deep sand bed> My plan is to buy a new 10 gal and drill two holes. I would like to run about 200 GPH through the fuge. <The 15 gallon?? Sounds about right Should be between 4-8X tank volume> Would you recommend 1/2 or 3/4 hose for the intake and return? <1/2 sounds about right but you might want to test it in a bucket or something of that manner> This will determine what size to drill the holes. <Of course> I am thinking of either a Mag 3 or 5 for the return pump. Which would you recommend or would you use a different pump? <See here: http://www.wetwebmedia.com/pumpselmar.htm I don't really have a preference> I would use a ball valve to adjust flow <Excellent> but just wondering if the Mag 5 might still be too much. <Not likely if you can afford it> It would be internal. <fine> My original idea was to use 4 12'' baffles on the fuge. <WOW!> Pretty much the common design used on most DIY sites. The 2 reasons for baffles would be bubble elimination <yup> and to separate the return so I could not overflow the top tank. <To slow water movement through the sump?> Would bubbles be a problem if the Skimmer is not in the fuge? <Shouldn't but really depends on the skimmer> Could I just elevate the pump on egg crate instead of baffles? With the 10 gal tank drilled and the extra volume of the 15(fuge) I do not think I could over flow the fuge but could still overflow the 10 if something slowed or clogged the intake so the baffles would limit the water that could be pumped back up into the main tank. Does this sound logical? <Hmmmm....> Is this to complicated? I have never built or even used a refugium or sump so I would like to do it right and would appreciate your input. <Do research more on this on our site and others. Ask this question of the many who have done this before you on the various forums out and about net> In the fuge I would move some of the LR into my 55 and some into the main tank. <????> I would leave everything except the Blenny and the 2 larger stars, and 1 hermit and 1 snail. I would like to use the fuge for Macro algae and all the little critters to help feed the main tank. <No need to put crabs, large stars, or snails in your refugium. Just amphipods and mysids with some of the various fauna available to the aquarist should suffice.> In the main tank I would also have a Penguin 550 PH and a HOB power filter. <Lots of live rock> Approximately 500 GPH in the main tank. <On a 55 gallon? sounds good but try to make the output more dynamic, more random> The substrate would be 3-4'' of oolithic sand. <Make it 4 inches or above> The corals I would like to add are 1 Open Brain and 1 Plate coral on the sand and in the rocks I would like mushrooms, xenias, zoos and starbursts as well as a few lbs of new LR. <sounds good> The fish would be the lawnmower (might move him to the 55), and a purple Firefish, if the blenny is gone a Citron clown goby. <OK> 1 peppermint or sexy shrimp. Would this be too much water movement for the corals above? I will try to place them according to their preference of water movement. <Exactly. The brain likes the least amount of flow> All advice, comments and questions are greatly appreciated by yourself and everyone else from this awesome web site <Do research our site for more on all the above questions. Good luck ~Paul> Thank you very much!! Walt

Flow dynamics - 3/8/04 Dear Paul Thank you very much for the help on such poorly conceived ramblings of a mad man. <Not really rambling or a madman. Your ideas were based on good science> I am sorry for writing such a confusing email. <No apology necessary> I must have been sober while writing the questions. <Ahhh. I try not write when sober> First the 55 is a FOWLR and my only reason for mentioning it was to move some old LR, the Blenny and possibly the Sally Lightfoot into. Much less confusing if I would have just left it out, sorry. The main tank reference was to the 10 gal mini reef and the 15gal was the refugium beneath the mini reef. I would like to have about 10 gallons of water in the fuge along with macro's and pods and mysis, 10 lbs of LR and deep sand. <Perfect. I love this idea!> I have done some research and feel there are 2 ways I think would work. First I would like to use 12'' tall baffles on the intake and return. This would help eliminate bubbles and isolate the return pump so I could not over flow the mini reef if something happened to the intake. <Perfect> The second would be no baffles and raise the return pump up high enough so that it would run dry before it overflows the mini reef. <Not seeing how this would work for some reason> The 200 GPH would be 20 times the volume of the fuge. Is that too much water flowing through the fuge? <Fine> I would add new LR to the existing LR in both the fuge and mini reef. <As long as it is fully cured> I would probably go with the mag 5 unless 200 GPH is too much. The Penguin 550 PH and an Aqua Clear 200 HOB filter or Prizm Skimmer( I have both available) would be on the 10 gal mini reef not the 55 gal. <Good enough> So all this would be in the 10. <Wow! It will all fit, eh?> I am worried this might be too much water movement of approx 500 GPH in a 10 gal. <Well, depends on the animals and their reaction. Might be too much though, the output of these filters does change once media is in place, flow dynamics etc> What do you think about the flow rate for the corals I would like to add? <Well, the corals you are listing in your previous email might react poorly to this amount of flow. Is there a way to throttle flow back with your plumbing or filters?> The Mini reef would be 4'' oolithic sand .2-1 mm or flamingo pink 1-2 mm, <Add a light dusting as a top dressing to keep the oolitic from lifting and blowing throughout the tank> 10 lbs LR, some assortment of the coral frags mentioned earlier and a Purple Firefish and a Citron clown goby. <Keep a lid on tight for Firefish> The only things I must have is an open brain coral Trachyphyllia geoffroyi and a purple Firefish. <Then I must say I think the flow could be an issue. If it can't be adjusted as needed through plumbing or pump then maybe select some pump or method that will allow for such> Once again sorry for the first confusing e mail. <Take care ~Paul> Thank you. Walt

Refugium turnover I have a 90 gallon that is cycling to be a reef tank....I am going to have a 20 gallon refugium mounted above the tank for macro algae and different types of pods...(I want a mandarin goby).....from what I have read and researched, I have found the some people say you should only have 1-2x turnover per hour? What do you recommend? Is that accurate. <That seems a little slow, however, it really depends on the inhabitants in the refugium. If you're planning on growing various species of macro algae, a turnover rate of up to 5x per hour may be sufficient.> I have a 40 gallon sump and I was going to half of it a refugium, but the water flow would be too much wouldn't it? <Considering I don't know what pump(s) you're planning on using, I have no clue. If you want further information, please do not hesitate to email us back with further information (mainly with the what pump you're using, how many gallons per hour it is, etc.) Hope this helps, Graham Stephan.>

Moving Water And Bringin' Up The Lights! Sorry I have two other questions...for water movement in my tank I had planned on putting the return in the back middle, maybe with a T since it will be constant. <Or, you could use an alternating current device, like the SCWD, which alternates the flow in two directions> Also, I had planned on buying 4 Rio powerheads. 2-200 and 2-600 and put them at opposite corners and heights of the tank. Then put 1 of each on one timer and one of each on another timer to come on opposite each other so there is some what of a variety of current. <Personally, I don't like the idea of running powerheads with timers. It's kind of hard on most of them, and the benefit derived may not be worth the hassle, IMO. Just run 'em all the time. You could, however, use external powerheads, such as the Tunze "Turbelle" models, which can be run on a timer if you wish. And, being external, they will not impart too much heat into the tank> My last question is regarding lighting. I plan on having 6 46.5" VHO lights which will be on timers in pairs to come on 2 at a time then go off 2 at a time to try to mimic the day. Would I want 3 actinic blues and 3 whites? Please let me know what you think. Thank you...Butch <Well, it really depends upon the life forms that you intend to keep. Mixing actinics and full spectrum is nice from an aesthetic standpoint. No right or wrong here. Just choose a lighting scheme that suits the needs of your animals, and go from there! Good luck! Regards, Scott F>

Adjusting a skimmer - 2/23/04 Well hello Paul, oops, I mean Pahulio! <Heheheheeee> Very cute! <OH?> Update: I took apart my Remora skimmer and cleaned out under the screw, (did I tell you this?). <Yep. I know very little about this skimmer but did look through the site a bit.> So far, not skimming any better, but I did go to the Remora site and emailed Jason Kim. I do hope he replies. <He will and if not him then someone will be in touch. Great company. Let me know if you don't hear from them in the next couple of days> I also went to www.drfostersmith.com and found lots of helpful info about wavemakers. <Yeah. Random pulsing is about it though. Nothing too special. Check out instructions on the Carlson's surge device (named after Bruce Carlson formerly the Director of the Waikiki Aquarium.) See here: http://www.breedersregistry.gen.ca.us/Reprints/MFM/v11_aug96/simple_surge.htm http://www.masla.com/reef/csm.html That is what we like to use in addition to our powerheads at the Monterey Bay Aquarium> They sound intriguing although quite a project that would entail a bit of rearranging of my rock and powerheads. <to get the best coverage then I think that you will have to do some arranging. I thought you didn't like the unsightliness of your powerheads, though?> I may purchase one in the future AFTER a bit more research. <Good girl. You get an A> I also purchased some Poly Filter. <Sweet. Me too. I bought four packages today.> I never heard of this product, but this is not surprising seeing how lazy I have been in the past to go out there and look around! <Works well. Many of us here at WetWebMedia headquarters enjoy and recommend this product quite readily. Let me put it this way, I have never had a Cyano bloom in the tanks I use it in> I do say Paul, I believe you just may have cured my lazy bug! <Not lazy.....just overwhelmed. Sounds like you have much going on and adding anything else to an already busy schedule is quite overwhelming to say the least!> I'm printing everything in site and have started a folder for my reef experiences. <Good to hear. I do the same> what do you say about that? <A+?> Take care my friend and do write back, <Will do> ...my neuro nets are getting quite accustomed to you. <Sweet. Thanks for being part of it all. You are on your way to being a Conscientious Marine Aquarist for sure. ~Paulito>

Carlson Surge Device - 2/23/04 Hey Pauly, this link is no good>>> http://www.breedersregistry.gen.ca.us/Reprints/MFM/v11_aug96/simple_surge.htm <Try now: http://www.breeders-registry.gen.ca.us/Reprints/MFM/v11_aug96/simple_surge.htm Needed the dash! Who woulda thunk?? Paulo>

Aquafuge pro Dear Sirs, I wrote earlier today w/ a question on flows for a 100 gl reef tank which Anthony promptly answered. I have the greatest respect for your team and hold your opinions above all others, <Thanks for the kind words!> please do not misunderstand me but I've just recently ordered a $990 tank thinking I had a good handle on things, but now I'm wondering if I'm getting in over my head (no pun intended). <Has happened to all of us.> Basically Anthony answered that I need 10x the system flow thru the sump to keep it from getting stagnant. <I am not sure what Anthony's exact comment was, but I am not sure that this was his intended interpretation. 10x water flow is ideal in the display. 10x would is also a good ideal for the sump, but that is 10x it's volume (~250gph min in the case of the Aquafuge pro). Many systems are designed so that all of the display flow also goes through the sump, but in this case that may not be ideal.> The sump is the Aquafuge Pro from CPR. I had e-mailed CPR earlier asking what pump they recommended and received a reply just a few minutes ago saying no more then 400 gph thru the sump, use a Rio 1700. <This sounds like a reasonable recommendation based on the size of the product, although I would recommend a similarly rated Mag Drive, Sen, Sedra, or Eheim pump over the reportedly less reliable RIO.> My dilemma is this: I have a very bad feeling that the tank builder is going to cut me short on the overflow capacity if I need 1000 gph for the sump alone. <Indeed, a tank with overflows that can actually handle that kind of flow is rare (and often impractical). This is largely why powerheads and closed loops are so commonly used.> I'm also heeding Anthony's advice on no power heads. So if I go closed loop w/ a separate pump and run it from the sump I will also need overflow capacity for that. <By definition, closed loop circulation does not pass through the sump. Water is drawn directly from the tank, through the pump and back. There are many design possibilities, and most do not require the use of a pre-existing drain.> Before I go back to my LFS tomorrow and say hold everything the tanks gonna be wrong, I would like your feedback on this situation. I do not want to offend anyone, I do not want to offend CPR or take any credibility away from anyone, but as you can see I'm getting some conflicting info. <Yes and no. Sometimes it is hard to see the "big picture". 400gph through the aqua-fuge is a good recommendation. 1000gph total in your display is a good recommendation. Since you can't move 1000gph through the 'fuge, you will have to make it up another way. Which way is best depends on your budget, how badly you want to avoid powerheads and other details of your system and hardware.> I want his tank to be right from the start, no band-aids or jury rigging if it can be avoided. <Kudos on trying to plan well! All to often we set things up just to get it done and then are stuck with poor choices.> What would be the recommended size of overflow holes for 2000 gph <You would probably need at least 3-4 1.5" drains to handle that kind of flow, which most folks would consider to be impractical.> or more and what are your thoughts on CPR saying 400 gph thru the sump? Maybe I'm way off on the whole thing, should I run some other type of filtration? Can it be that mud in a sump can't handle 1000 gph? I'm guessing the CPR system would run similar to the ecosystem are the flows that low for those? If you feel this note could cause some problems w/ CPR or whomever maybe it shouldn't be posted. I just want to have the best experience possible w/ this new adventure, but having some trouble w/ the foundation. Your the only ones I know that have the experience to provide and educated answer. Respectfully, Sam Marrone <I removed the reply from CPR since it wasn't really relevant to the discussion and they made a good recommendation that is already covered here. My personal preference for a "typical" system with a refugium placed under the stand is to provide appropriate flow through the refugium (in this case 400gph) to the display with an appropriate pump. A single 1-1.5" drain will handle this fine. Then, apply a closed loop to provide the additionally flow desired to the display. A second drain can be plumbed directly to the inlet of the circulation pump (drain hole must be submerged at all times, no sucking air!), and the return line plumbed as desired. I hope I have explained all clearly and adequately. Best of luck, and feel free to write back for clarification. Adam>

Pumping Up The Flow! (Increasing Circulation) Hi there Crew, <Hey there! Scott F. with you today!> First of all I must congrats Mr. Fenner on such a fine book which blew a fair few of the myths away from the mystic art of marine fish/reefkeeping, and well done to you all for a wonderful and informative site. <We do owe a debt of gratitude to Bob. His book definitely shapes our overall philosophy at WWM> I hope you will bear with me with some of the questions I would like to throw in your direction in the near future. (That is if you don't mind?) <That's why we're here! Ask away!> I would like to know how I can "usefully" increase the water turnover in my 6x2x2 tank with a 20 G sump. At the moment this is a mainly FO setup, the tank is bottom drilled with two holes which allow between 600-800 gallons per hour maximum turnover with an ocean runner 3500 Aqua-Medic pump. I do have 3 powerheads to add some flow in the tank. What I would like to do, is to get rid of the powerheads, they junk up the system and would like to add a larger pump to the sump with an added hang-on overflow to the sump to increase the turnover. <Well, I am personally not a huge fan of external overflows, mainly because they are prone to failure at the most unfortunate times. If you don't like the powerheads inside the tank, I'd utilize some external powerheads, such as Tunze Turbelles or Geminis, which put out serious water flow, and don't clutter up the look of the tank like internal powerheads do, and they do it with very little power consumption!. You could also look into constructing a "closed loop" but it may involve draining the water before drilling the tank. A serious project.> At present I have 2 inches of rough crushed coral (too course) and intend to make this 5" deep with live sand. Would you add a filter plate (undergravel type) under the live sand as a plenum? <I would follow generally accepted concepts of plenum construction, such as those advocated by Bob Goemans and others. You could visit Bob's excellent site www.saltcorner.com, for more information on plenum concepts.> I have two trickle towers I would like two get rid of. Should I just take the bioballs out of these slowly as I add the live rock? <Yep- that's a great way to do this...Let the live rock do the "filtration"...> Also I have two protein skimmers, a Berlin Classic driven by an Eheim 1060, and A Turboflotor 1000 (Which incidentally takes out about 4 times the amount the Berlin skimmer does!) I would also like to hard plumb the entire system and to add live rock (slowly, as explained above) maybe 140lbs. (Would this be enough?) <All depends on what you're trying to accomplish. I have become an advocate of "less" live rock than usually utilized in the past (like a half a pound or so per gallon, rather than the typical 1-2 lbs per gallon. I find that this creates a more open rock structure that provides room for corals to grow and fishes to swim, and keeps a higher volume of water in the system. And, as Anthony likes to say, "Dilution is the solution to pollution"...It's all subjective, however- do what works best for you. The good thing about using less rock is that you can always add more down the line if you should deem it necessary.> I Sincerely hope to hear from you soon. By looking through your site you must be doing more than has ever been done before to inform the general public (such as me) about how to protect our precious fish and reefs, and if they intend to keep these animals- to be more aware of the life forms likely to survive in captivity. Well done indeed. Simon UK <Glad to be of service, Simon. We're all learning together! Good luck, and feel free to call on us again any time! Regards, Scott F.> - Circulation and Sumps - Hello Crew at wet web. Can someone answer a question or two for me? This is my plan. The aquarium is 280gal empty fish only with live sand, maybe some live rock. I have a dolphin amp master 3000 with a head pressure of seven feet. With displacement I should be able to turn the tank water over 10 time an hour. I have ordered an aqua C ev400 skimmer. I plan the following: water from display into a sump to a compartment which may house activated carbon if necessary, then to skimmer, then to live rock, then out to display powered by the amp master. Will the water flow be too much for the live rock resulting in nitrates which I do not want? Will water in have too many bubbles for the skimmer and if so, is that OK? <Hard to predict - may be a lot of bubbles, but this will likely not adversely affect the skimmer.> Is this series of events logical? <It's not illogical.> The level will hopefully be around 8 inches. This is what the EV 400 needs. <As long as it stays consistent, you should be all set.> Lighting for the live rock will be a fluorescence like Doro- Test Vita light. What wattage should this be? <If you're looking for Vitalites, then you're committing yourself to 40 watts.> Is this lighting sufficient for the live rock? <Probably... live rock really can go unlit, but the coralline algae will likely die out if so. The amount of lighting is really up to you.> I intend to turn it on when the display lights are off at night. Did I say two questions??? I could try - in a few more! Once again - Thank you Chris <Cheers, J -- >

Circulation - 2/3/04 Thank you Paul. <No problem> After I send this letter I'll visit the link you sent me. To answer your question, "why did I put the airstone in the tank............?" I put it there because I wanted more water movement in the back of the tank where it seems to be growing black slimy algae. Was this an okay idea? <I would try to get some stronger water circulation to the area via a small powerhead. Actually, come to think of it, I would increase the overall circulation of your tank. Either with a stronger output pump or random powerhead placement. Thanks Pam, for being part of it all ~Paul> Thank you! Pam More about circulation - 2/3/04 Wow Paul, you're fast! <Well...I wouldn't say that> I do have 4 powerheads in the tank as well as the skimmer and an aqua clear filter to add to the water quality via chemical filtration and movement. <Wow, more than I anticipated> The tank is 75 gallons with about 80 lbs of LR and 50lbs of sand. <Sounds nice> There just seems to be many nooks and crannies that are perfect for growing this stuff, (black slime) I really do hate the look of powerheads, <As do I. Really detracts from the overall natural look and feel of a reef> but my expertise with salt water is a bit limited,(3 years) and power heads seemed to be the easiest way to go. <you as many years as I in saltwater...> Since I've got you here, I'd like to pick your brain a bit more? <Ewwwwwww> I have also noticed strange growths in the darker corners of my tank. They vary in size from peas to quarters and they are perfect little balls of what looks like cream colored rock covered with fuzz. I can't reach them to touch, or I would. What do you think? <Sounds like Leucetta sponge. A common hitchhiker on live rock> By the way, here's a small pic of my tank, and while you're at it, could you PLEASE identify that fish between the clowns? <from this pic it is a little difficult for me to positively identify the species. Looks like a damsel type fish though. Not sure. Do you have any better pictures??> I bought 3 of them last year and I forget what they are! Thank you! <Thank you. ~Paul> Pam

GPH question.. 2/2/04 What gph rating do you recommend for a 180 gallon tank? I'm going to have it "T" off to both returns from my sump, so its going to be one pump doing all the work. I plan on going with an Iwaki, and they have one rated for 1500 gph and 2000 gph @ 4ft. Any good advice will be greatly appreciated... <As a general rule, total water flow should be 5x the tank volume for a fish only tank, and 5-10x or more for a reef tank. The problem you may encounter is weather your drains will handle such high flow. You may have to choose a smaller return pump, which has other advantages such as less noise, less power consumption, and lower cost. You can make up the difference with powerheads or closed loop circulation. Hope this helps. Adam>

Circulation - 1/30/04 Dear WetWebMedia Crew, First and foremost, I wanted to say what an amazing website you have created. <Thank you for being part of it> It is insightful, informative and innovative. Thank you to you all so much for taking the time to help the general public in the manner that you do. Your "words of wisdom" have been like a bible in my fish caring regimen. <great to hear> My question has to do with water circulation. <OK> I have read your Marine Systems Circulation article by Mr. Calfo as well as spending the next couple of hours going over the FAQs but have not had success in answering my question. <Really? We have covered this to quite some degree.... Well, now I think we will be covered with the help of your question> I have a 100-gallon tank (72x18x20) with live rock, 7 fishes and six soft corals. For my circulation, I am running a Supreme Mag-Drive 950 as the main return pump, rated at 950 gallons per hour with 0 head, my total head pressure is about 5feet. This pump is returning water from an under the tank sump (60 gallons) and accompanying this are four MaxiJet 1200 power heads. My current setup is to have the Mag-Drive on the right hand side of the tank moving water straight across the top (at or near the surface) to the left side of the tank where my overflow is. <OK> The four MaxiJets are at the top four corners of the tank aiming towards each other and pointing downward to the middle of the tank (top right-front point to bottom left-back, top left-front is aimed at the lower right and back of the tank, etc.). Water circulation seems to be random, causing my corals sway back and forth in a non-laminar pattern. <Good> What I do noticed is that the sand on either ends of my tank turn brown with a light coating of algae while the middle, middle front and middle back of the tank stay white. <Well, there is a pocket of minimal circulation to be sure> My rockscape are two mounds with an opening in the middle (like two triangles about two thirds the height of the tank with a foot long gap between the two mounds in the middle of the tank where no rock occupy). <very well> I have on average about three inches of space between all the walls of my tank and rocks for ease of cleaning. <Super smart> This rockscape is best described as having two triangular rock mounds in the middle of the tank and a 12" gap separating the two. <Got it. Excellent description I might add> I have tried placing the power heads in many different patterns but am still having problem getting all of my sand to stay white. <add to little powerheads with some soft of extenders in that area or up you return pump from the 950 and see if what effect that will have> My temporary solution is to disturb the sand at the ends of my tank once every third day to prevent the algae from growing. <Well, sometimes needs to be done> I have read your articles on overfeeding, protein skimming and good water quality and have tried to stick to your guidelines. <Excellent> I feed twice a day for about 90 seconds and made sure all food is consumed. ,Good rule of thumb if your fishes require you to feed this way.> I only use distilled water for water changes and make-up water. I have a EuroReef CS2-8 protein skimmer and my lighting is Custom Sealife PowerCompacts (four 10,000K, 96watts daylight bulbs and two Ultra Actinic also at 96 watts, totaling 576 watts). <OK> I am not sure how to achieve a good circulation of my tank to prevent algae from growing on the sand at either end. Should I purchase more powerheads, remove some, purchase different ones or place them. <I would add tow smaller ones to work the areas of your tank where the algae accumulates or I would at the very least increase the return pump. Be sure you are turning your water over anywhere from 20 to 40 times your tank volume maybe even more in some cases> in a pattern I haven't thought of yet? <Hard to say if your pattern could be changed even with your excellent description.> Any advice you can provide would be invaluable! <Hopefully my suggestions will assist you in making the best choice.> Thank you in advanced for your help, Tim San Jose, CA P.S. Thank you Mr. Fenner for signing your Reef Invertebrate book during your visit to Aquatic Gallery in Milpitas, CA. <Glad you enjoyed that. I had a hand in setting that up for Bao. He is a great source of information as well. We are very fortunate to have the Aquatic Gallery in our area (I also live in San Jose)> It was a joy to meet you in person!

Goin' For The Flow! (Water Flow) Hello all, <Hi there! Scott F. with you tonight!> Your website is a great reference. <Glad you like it! We have a blast bringing it to you!> I am setting up a 75 All-Glass Aquarium with a built in overflow system. The manufacturer wrote back to me advising that the overflow system is rated for 600 gph. Given it is traveling approximately 3 feet up from the sump and I want to return the water through a PVC return manifold. What GPH of a return pump should I buy 600, 800, 1000? I am assuming the pump looses some pressure traveling up and through a manifold system. I was thinking of using a Iwaki pump, I hear these pumps are reliable and quiet. <I use Iwakis myself, and love 'em. They are not the absolute quietest pumps around, IMO- but they are insanely reliable, and move water very well. You might want to look into an Iwaki MD 40 or an MD55. You can always bleed off some of the flow if it's to much> Is the external pump a better idea than the submersed pump for the sump return? Given the flow rate will be 600 gph, this is not enough for a reef. What do you recommend to increase circulation power heads, a submersed pump in the display or drill the back for a closed loop circulation system. <Ahh- a better idea still. Yes- you can use external powerheads, such as Geminis or Tunze Turbelles, or internal pumps, such as the new Tunze Stream pumps ($$$- but they ROCK!). Or- you could construct a closed loop or manifold, as you contemplate. Still another thought would be to use a Sea Swirl plumbed to your closed loop to oscillate the return to the tank...A million possibilities, only limited by your imagination, your budget, and your electric bill!> Last I am looking at the AquaC EV180 or the ETSS Reef devil protein skimmers. Which one would you recommend for a 75G reef (40G long sump)? <Both are excellent, but I'd give the edge to the Aqua C for ease of use and maintenance> Thanks in advance for your help. <A pleasure! Regards, Scott F>

Do over? 1/26/04 Hi Anthony, Thanks for the I.D. Will keep an eye on him (the keyhole limpet, actually there is a junior now too) and the coralline. <ah, good... and likely little to watch/worry about> If you (or whomever is manning the turret today) have the time, couple of other questions. <Sure... I'm actually answering from temperate San Diego now... working on (Bobs) images for our next book> Taking all of my vast experience (6 months :o) and all of the incredible input from you and the rest of the crew and the site, have requested and received permission (the wife) for a "do over" on my tank set up. New (wider) tank, sump, stand, plumbing, sand bed. <She's a keeper... buy her flowers and think about marrying her again> More importantly, want to take a slower approach. Have had an assortment of what appear (from daily reading of FAQs) to be the typical newbie problems, <yes... alas, yes> learned a lot from them, and realize now that there are structural problems with my setup that I can either address now or struggle with/be annoyed by forever. <OK> The go slower part is based upon the realization, which probably comes to most a lot quicker, that a saltwater tank takes a looong time to really become stable/conducive to housing vert's and inverts, and the things you do in the beginning have a lasting impact on how difficult the tank will be to maintain and how good a home you are going to be able to provide the critters. <all true. Some of the best tanks were started by patient aquarists that did not add a single fish or coral form the first 6-12 months. Instead planning for the long haul and enjoying a remarkable evolution in the tank with the live rock, sand, etc in the process.> Although I started this slower process and the new setup a several weeks ago, by setting up a second tank (55g) with live rock, oolitic sand, and a detritivore kit from Inland Aquatics (and leaving this tank alone for at least 5-6 months), < you will not regret it my friend... some fresh live rock too> it was all crystallized for me by an article I read that was linked in the daily FAQs. The link is here, for any newbie that missed it: http://www.reefkeeping.com/issues/2004-01/eb/index.htm <thanks for this> Especially Myth 15, about cycling, stocking, and nitrification. Don't know if you agree with all of the points made here, but it really hit home for me and thought that anyone new to the hobby should at least give it a read. Enough running my mouth. Time for questions (if you are willing). One of the things I struggled with in my existing setup is trying to get all this turnover in the tank, relying primarily on my return pump (don't want powerheads). My question, how much circulation do you really need through the sump, versus total circulation that can be delivered through a closed loop? <ahhh... you have hit on the quandary exactly... folks often confuse the circulation needed with the turnover through the sump. They are/can be two entirely different things. The display needs 10-20X turnover which can include any combination of in tank/closed loop pumps and/or sump return pumps. But the sump itself has no requirements for flow if its acting simply as a sump> I read an article stating that anything more than what you skimmer will process is not necessary, and the rest of the 15x to 20x that I am shooting for can be provided through a closed loop. Right now I am trying to push about 1,500 gallons per hour through the sump (100g display), but the skimmer will only process about 300 gallons per hour. <if all water goes through a skimmer chamber/partition... then you can run more than 300gph through> With all this flow thru it is difficult to put in any kind of settling chamber, set up any sort of in-sump refugium (if I go that way), too much plumbing (and associated salt creep) with all these overflows (5), and various and assorted other problems. Are there other benefits to getting more circulation via the sump/return pump (any more than the skimmer can handle), <nope> vs. a closed loop with your teed manifold? <a better choice> Am I missing something? <beer> That's it for now. Don't want to abuse (more than I already have) what is truly a privilege. You guys and gals are the best. Jim <wishing you the best my friend :) Anthony>

- Circulation Ideas - I would like to upgrade my 55gal reef tank to 120gal AGA tank. Instead of buying the more expensive version with undersized overflows, I'm thinking about buying the regular version of this tank and having it drilled to my specifications. <You do know All Glass has a new overflow on their tanks which can deliver more water...> I'm thinking about employing Anthony's water return manifold and also the built-in glass overflow. I would like to design the system so that it has both an open and a closed loop for circulation. Open loop: 2" bulkhead drains from the built-in overflow into the sump, Velocity T3 (I already own this pump) returning the water back through another 1 1/2" bulkhead to one part of the return manifold. The pump will also feed the Turboflotor 1000 (~250gph?) and the calcium reactor (probably <1gph). <Hmm... might be more wise to have a separate pump for the skimmer.> Closed loop: another 2" bulkhead (not in the built-in overflow) drains directly into the pump intake and is pumped right back through another 1 ?" bulkhead into the second part of the return manifold. 1) The manifold will be split into two parts, one for each pump. 2) All holes for the bulkheads will be drilled in the left/right upper corners of the back wall. 3) The intake for the closed loop will be drawn from the lower part of the tank, bulkhead on the (I will use pvc elbow, pipe, and a strainer inside the tank, would like to get some corals like start polyps to grow on the pipe to hide it). <Do make sure all this will be serviceable, using true unions, perhaps even with redundant valves - if there is a failure, your tank could spill its guts.> 4) For the closed loop circulation, I've been thinking about getting the Dolphin 2100 HD pump (2100gph @ 0' head). My question is if this is too much water movement. <Perhaps from one point-source... but on average, it's not that easy to have too much circulation.> I suspect that I could get Iwaki 40RX (1344gph @ 0' head) instead. The other questions is if two 2 3/8" holes and two 3" holes in the back hole is too much and this can weaken the glass. <You will have to work with the manufacturer to properly answer this question - my thinking would be yes, but I'd like a more definitive answer than just my opinion.> I was thinking about having the holes drilled close to the corners where the stress in the glass is probably the smallest. Please have a look at the attached schema. <Yes... be very cautious about developing a siphon with that closed loop intake.> Thanks, Petr <Cheers, J -- >

- Circulation Ideas, Follow-up - I heard about the AGA new Megaflow, but I also heard that they have not increased the size of the holes. From what I know they moved the overflows from the corner to the back wall, introduced the DURSO pipe, and increased the size (skimming length) of the overflow. They customer rep. emailed me stating that they drill them with two 1 3/4" & two 1 1/2" holes (1" & 3/4" bulkheads). I guess that through 1" bulkhead, I can drain about 600gph, right? <Think 900 GPH is the limit for a one inch pipe.> So that would be about 1200gph total (10x the volume of the tank), which is about a half of what a reef tank of this size needs, right? <Personally, I always rely on addition pumps in the tank to boost my circulation. My tank has a sandbed in the sump and too much water flowing through it will put the sand into the water. This is just me of course - your plan to add the closed loop et al will give ample opportunity to improve circulation.> Oh, I forgot to mention that I would drill several small holes into the intake closed loop pipe about an inch or two below the regular water level. That way in case of a power failure and/or a crack in the closed loop plumbing, the water level would drop and air would get into the pipe and break the siphon. <Sound good.> --Petr <Cheers, J -- >

- Flow Rates, More Follow-up - Thanks FYI - Mag drive 1200 @ PetSmart in the US is $99.00... Same pump up here in Canada is $225.00 CAD. What sucks is that after you take into consideration for the shipping, exchange and duty exchange, the US pump is about $210.00 CAD So much for Free Trade eh <Take off! That's a lot of cash - can't you get Eheim pumps up in Canada? Cheers, J -- >

- Flow Rates - Post Script - I was talking to my LFS and he suggested that I stay away from the Mag Drive and was suggesting a Jennex External pump. <Perhaps they meant GenEx... should be easier to find with that name.> Are you familiar with this model and if so can you direct me to a website that might have some information relative to it? <I've never used these - I have used Supreme Mag pumps extensively and think they are a good value but do eventually let you down after a couple of years - I've had several refuse to start after being turned off for a water change. I make up for this by having more than one of the same pump around - realize that for what you are paying, that may not be practical. Speaking of which... I'm pretty sure Big Al's is based in the Great White North - perhaps you should check pump prices with them: http://www.bigalsonline.com/ > Thanks Chris <Cheers, J -- >

- Flow Rates - Post, Post Script - They are actually higher...for the mag 12 they charge $245.00 CAD... <Ouch!> I've found smaller guys that will do $225.00 but I still have to add the 15% on for taxes. <What a pain.> Is the Eheim an inline pump ? <Yes, or rather Eheim makes many things including inline/submersible pumps. Cheers, J -- >

- Flow Rates - Hi guys, Hope all is well I hate asking you these questions as they are undoubtedly in your library, however it seems that they all relate to reef tanks Anyway my questions are in regards to flow rates I have a 110 gallon fish only predator tank going. My filtration is a sump with a power head pumping the return and am thinking about hard plumbing a pump in there for both higher efficiency for both flow rate and noise reduction I see mention of going 10 - 1 so simple math would dictate a pump pushing 1100 gallon per hour... is this the minimum or the max... should I be looking for something with a higher flow capacity. <10x is a reasonable goal - the fish will likely be able to deal with much more, but in a practical sense, 10x is worth shooting for.> Your articles also indicate having more than 1 direction of water flow...With being a fish only tank should I be worried about this (am thinking that I should add a power head onto the opposite side of my tank) or will the single return continue to suffice. <Yes, the most practical way to bolster the circulation from the main pump is with powerheads in the main tank - for a 110 I'd have at least four, or if you have the means a couple of Tunze Stream Pumps.> As always, your thoughts and idea is greatly appreciated Chris <Cheers, J -- >

- Flow Rates, Follow-up - Hi J Thanks for the response So the plan is to put a Mag drive 1200 inline with my sump and I'll continue to use my existing power head pointing inward from the opposite corner (Both returns would then be from the top corners pointing inwards. Do you think that I should continue to have the power head pull water from the sump increasing the gph flow rate or should I just have it recycling tank water <I'd just use it to recycle the tank water.> Let me know, thx Chris <Cheers, J -- >

A Moving Experience (Water Circulation> Thanks for the previous help, but there is something else that I have just realized, and seems like it can be a big problem in the future. <Well, let's tackle it now! Scott F. with you tonight> When I first purchased my 220g tank the LFS "set me up" with an AquaClear wet/dry 200 system (overflow box-I have no drilled holes) and a little giant pump. Well, I was thinking the other day and did some research and figured out my main circulation is only about 800 gph. At least that's all the external overflow box can hold, what got me thinking about this was the fact that the box seems maxed out and overtime has slowed flow rate which causes my tank level to rise. <Definitely something worth correcting> Now I've read Mr. Fenner's book, and spent about three solid days on your site looking for what I should do. I realize 800gph is way under the recommended flow rate. My tank is fallow for the next couple weeks but here is my future stock list: Mac angel flame angel harl. tusk flame hawk 2-3 butterflies one tang large school of Chromis plus I have over 200lbs of Florida live rock an average of two inches of CaribSea sand (I believe) and a Euroreef CS12-1 (rated for 300g) between my overflow and wet/dry <Excellent skimmer! BTW- If it were me, I'd dump the bioballs in the wet-dry...> and 3 300gph powerheads. I'm sure your about to tell me to upgrade my circulation, but I'm not sure how to. <Well, more circulation is not mandatory, but it is beneficial to many fishes and any future corals you may plan on keeping> I realize not only are my fish going to be less healthy and happy, but I'm also sure that I'm not getting the most out of my large skimmer. <Gotta work that skimmer! It's a good one!> I guess my questions start at: will my biological filtration be sufficient if I get rid of the wet/dry and incorporate a refugium? <Should work fine with all of that rock. Besides, you can use it as a sump to keep chemical media, macroalgae, etc.> I'm hoping my skimmer and +200lbs of live rock will be fine if my fish are introduced far enough apart. <Should be fine> But will I miss anything about my wet/dry? <Nitrate accumulation!> Also, what can I do about improving my circulation? External overflow boxes are my only option because I'm not even sure if I can drill my tank, and if I could, I can't transport it. I've looked at several brands of external overflows: Lifereef, CPR, etc., all seem to max out at 1400-1600 gph, can I use two and should I? <Personally, I'd employ some external powerheads, like the Tunze Turbelles, Turbelle Streams, Gemini pumps, etc. These things rock! In fact, a Gemini puts out about 960gph, and some of the higher-end Turbelle Stream pumps can put out over 3,000gph! We're talking internal circulation here- with minimal electrical consumption! Good stuff!> From what I've read, I need about 2200gph of main circulation, does this mean that just one overflow at 1500gph is not enough? <Again- I'd use the aforementioned external pumps to move the water. A slower flow through your sump means a longer contact time for your skimmer- which means that it will operate with greater efficiency. I wouldn't sweat it at this point...> Is there another option? <As above> My tentative plan is to buy two external overflows which would give me a total of around 3000gph and I'm looking to buy a Mag pump rated at 2850gph at 6ft. But this is all tentative, if possible. <Try external pumps...> Thanks again, Brandon <My pleasure! Regards, Scott F.>

A Moving Experience (Pt. 2 ) Thanks for the help, but I'm a little confused. You're saying that internal powerheads are a better answer? I looked at the Tunze Stream pumps and those are rather expensive, more expensive than me buying the overflows and a Mag pump. <True! But there are less expensive alternatives, such as Gemini external pumps, and others.> My plan was to buy two AquaClear prefilter boxes rated at 1600gph for 70 a piece, then buy a Mag 36 pump for about $150. But mainly, I would like to know, if I raise the circulation to my sump from 800gph to 2500gph, will this hurt the skimmer's performance, that is located in the sump? <It is possible that the more rapid flow of water through the sump can decrease skimmer performance> You stated on the last reply that it needs more contact time, but isn't that just for the pumps that are directed into the skimmer? <Well, if our overflow is pulling in more water, you're going to have to pump it out somewhere, so a more powerful pump is generally needed.> It seems to me that a skimmer in a higher flow area would be able to extract better. Thanks, Brandon <Lots of opinions on this. Actually, level flow and longer contact times seem to be better thing for skimmer performance. I like higher water flow inside the tank, myself. You could try either idea and be successful. It's just important to size our pump's flow to the overflow's capacity. Good luck! Regards, Scott F.>

Flow Patterns... Hi Scott <Hi there...> How r u? <Doin' great!> I mentioned to you the other day that I have two 1100l p/h powerheads in my 350l tank. <yep...!> I have them opposing each other causing a good flow. <A good technique!> I was thinking of adding another powerhead to the back of the tank just to blow across the floor so that unwanted debris do not get a chance to settle. Do you think this is necessary, I do perform my water changes weekly where I perform siphoning of the surface gravel as well? <Not "necessary", but nice idea. And, flow is no substitute for water changes, IMO> Thanks, Ziad <You're quite welcome! Regards, Scott F>

- Circulation and Diatom Blooms - Dear Bob, Jason C., or whomever: <JasonC again... greetings.> Just wanted to thank you for your reply to my recent questions. My 180 gallon marine tank is now up and running and so far all is going well. I do however, have a question or two about a light brown coating beginning to appear on the sand substrate. The tank has been running now for about one week, and the sand substrate has finally settled down and the water is slowly clearing. However, a light brown film is developing on the substrate that I will assume is a diatom outbreak. <You are correct.> I am surprised by this because I have taken every measure known to prevent this from happening. <Not necessarily 'preventable' but often the first part of a series of succession... to be followed by other green algaes. Likely you were not able to rinse the new substrate as well as you might have thought.> Please note that this setup imported about 30 gallons of water and roughly 50 pounds of mature live rock that I had from another tank that I broke down and sold. In addition, the new water is 100 percent RO/DI water mixed with Tropic Marin salt, an additional 110 pounds of live rock was purchased cured and hand-picked by myself, a Euro Reef CS8-1 Skimmer has been going from day one, a filter bag with Phosguard is being used just beneath the water return in the sump, and the water flow in the tank itself is more than adequate with two strong return flows from the Mag 18 pump and two additional MaxiJet 1200 powerheads. Three fish (a purple tang, pygmy angel, and Scott's fairy wrasse) were brought over to this tank from the aquarium I broke down. I ran a series of water quality tests and all seems well: 1.0238 specific gravity, 8.1 pH, 9 Dkh, 0 ammonia, 0 nitrite, 5 nitrate. Here are my questions: If this is a diatom bloom should I simply ride it out and not be too concerned? <Is what I would do... am doing, just moved from one tank to another myself and am experiencing similar circumstances.> There are no corals in this tank, only live rock, some mushroom anemones, and the three fish. Should I reduce the photoperiod? <Will have some effect.> Presently, I run 120 watts of actinic fluorescent from 12 hours, and 192 watts of power compacts 50/50 Smartlamps for 10 hours. Adding additional flow to the tank seems unnecessary, and if the water flow is too low the sand gets disrupted and sent into the water column. <I would disagree... having been diving on only a couple of reefs, what is immediately obvious to me is that there is no practical way to have 'too much' circulation. Most reef fish are accustomed to circulation rates of tens to hundreds of millions of gallons per hours... sometimes per minute.> I was considering a couple of the white sand sifting starfish, but I'm not sure how many for a tank of this size. <I'd skip these and instead get your hands on some Nassarius snails.> Are these worth the investment? <Not in my opinion... will destroy much of the useful fauna in the sandbed.> By the way, the rock and glass do not (yet) show any signs of this growth, so I'd like to keep it in check right now if I can. Any suggestions? <More circulation.> Thanks for all of your help. Sam M. <Cheers, J -- >

Searching For The Sound of Silence! Hi , I hope you can be of assistance. <Will try! Scott F. with you today!> I have recently bought a new aquarium. After setting up the Euro-reef CS8-2 skimmer in my sump, the noise level is unacceptable. The system has 3 pumps , they are Mag 9.5 . The system is so noisy ( due to overflows that sound like Niagara Falls , dripping and splashing in sump and hum of 3 pumps. <Ohh, no> What can I do to substantially lower noise level, can cabinet floor be lined with rubber to decrease noise?. I have yet to pick up a canopy as new lighting is being added but I doubt if the canopy will decrease the noise level from the overflows ( glass tops are in place). Aquarium is in my living room and one cannot even hear TV due to it's noise. Unable to sleep on floor beneath equipment as it sounds like a washing machine running over my head. <I would consider constructing a "Durso Standpipe", which is essentially a cleverly designed standpipe that is designed to reduce noise. Do a search under the above and you'll find some how-to sites, as well as a site where you can order 'em right from the inventor, Richard Durso (the URL escapes me now...)> Any help would be appreciated , the LFS has been little assistance. I see beautiful aquariums in magazines , how do people deal with the noise from equipment? <Well, some noise is unavoidable-but you can utilize equipment that is designed to operate quietly, such as pumps (people like Dolphin Amp Master pumps- quiet and powerful...> I have read so many of your columns and have never seen this discussed . Help, I am desperate. Sorry to sound so frustrated but I have just invested $4000 for this system. <I understand! I think that the modified standpipe will make a considerable difference in the noise level by itself. Extra insulation and possibly utilizing a different pump or pumps can take care of the rest of the noise. Unfortunately, it may involve more $$$, but it can let you enjoy your system in peace> Thanks so much. Leslie Conrad <You're quite welcome! Good luck! Regards, Scott F>

A Suggestion x 2 I've just finished reading your book about Reef Invertebrates and I look forward to reading the next two volumes. <Thanks kindly... we're looking forward to delivering vol. 2 later this summer> Based on what I read in the book plus some articles on your website, I have a question on lighting and water movement. I'm running a 125 gal tank with four 96 watt Compact Smartlights (Custom Sea Life). I was running the 50 percent antic and 50 percent white in each bulb. Your book mentions normal life in the aquarium is captured near the surface and probably doesn't need the antic blue. <correct... your lighting scheme is attractive, but likely bluer than you need. No worries either way if growth is not primary> So, I'm thinking of changing two of the bulbs to the 10,000K daylight bulbs and keeping two of the 50/50 bulbs. It's a community tank with live rock and sand, some coral such as mushrooms, star polyps, a couple of leathers, and it has some inverts such a cleaner shrimp, sand sifter star, peppermint shrimp, hermit crab, serpent star, and a few fish such as yellow tang, mated pair clownfish (which lay eggs about once a month), cleaner wrasse, anyway, that's the jest. I think I'd get better light with at least two 10,000K daylights. Any thoughts? <agreed> On water circulation, based on the advice in your book, I added another power head to break up the linear flow I had before. I'm already seeing improvements! <outstanding!> The question is, I heard that in their natural environment, most fish and such find quiet places to sleep at night, but in an aquarium, there normally aren't places like that and so it's best to turn off the power heads at night. <not at all... and not exactly true either. The ocean does not have a bedtime per se, not can the fishes find quiet harbor at will... but even if that were true, that calmest seas are far more dynamic than our aquaria. Shutting off the power heads at night could be very harmful. At least reducing gas exchange and oxygen saturation> The only circulation and water movement at night is from the return line from the sump. So, I've had my power heads on the same timer with the lights. With your emphasis on water circulation, I just wanted to make sure this is sound, or should I keep the power heads on at night? <max water flow full time please... the fishes will be fine :)> Thanks for a great book and good website information! Bob <with kind regards, Anthony>

Bubbles 1/1/04 I have a 72 RR Oceanic bowfront, and an Iwaki MD40RLT for the return. The problem I am running into is that the return is producing bubbles everywhere in the tank and clouding it up. I temporarily switched to an Iwaki MD20RLT from another tank with no problems whatsoever in this same setup, and using the same tubing. The sump is an Oceanic Model 1. There are no leaks, as I have checked everywhere and used Petroleum jelly where possible, and I also have used a sponge prefilter to attempt to reduce any other bubbles. However, neither of these methods have worked. Is this pump too strong for the return drain of the tank, and therefore producing these bubbles? I am using 6 feet of head total. Any advice is much appreciated. <Hi Brian. Adam here. I would suspect that one of two things is happening. Either your drains are producing a lot of bubbles that are being sucked into the pump or the inlet of the pump is vortexing (looks like a whirlpool above the pump inlet). Try placing a downward facing elbow on the pump inlet inside the sump or increasing the depth of the sump. You could also try placing a valve on the outlet of the pump and slowly decreasing the flow until the problem goes away. An Iwaki 40 is a lot of pump for a 72! HTH. Adam>

- Too Much Circulation? - HI Crews, Sorry to bother you guys again. This is my questions. My tank is 46g FOWLR, a Emperor 400, a Remora. I just added a Maxijet1200 PH to increase water circulation last night. Since then, the small feather duster that is on my LR does not open up anymore. Is the water circulation too strong for them? <Quite possibly.> My Emperor give 400gph, the Maxijet PH is 295gph and should I count the Remora? <Yes.> So it is about 15X circulation and I figure out that it should do more good than harm right? <Yes, but given the size of your tank, this could perhaps be too much turbulence/agitation of the water. Feather dusters do live in areas of high flow in the wild but the sudden change is probably part of the problem. Give it a little more time... see what happens.> Also, last night, I noticed the head of my cleaner shrimp has some black mark/dots on it on both side of the shell. He seems to be as normal and very active during feeding time. Anything I should be concern about? <Nope.> Bok <Cheers, J -- >

- Circulation and Calcium - Hello, I currently have a 30 gal. reef tank with a mixture of hard and soft corals, including a maxima clam. I will be moving up to a 55 gal. and would like to know how much water movement I need. <Ten times the system volume, turned over every hour is a reasonable goal.> The tank does not have a sump so I will be using either the Hagen aqua clear 500 or 300 box filters rated at 500 and 300 gph respectively. The filter boxes will be filled with live rock rubble. I am currently using the small Prizm skimmer but will be upgrading to the remora skimmer with the MaxiJet 1200 pump, which I believe is rated at 295 gph. <The flow-through rate on this skimmer will be lower than the full output of that pump.> Eventually in one year I will be moving and will be setting up a 75 gal. reef tank with a sump, will the remora work for this size tank as well. <Yes.> One last thing, I currently use SeaChem reef advantage calcium to maintain calcium levels and use Kent marine super buffer and my calcium levels and alkalinity have remained stable and my hard corals and clam healthy. But I am confused about reef buffers, marine buffers, and reef builder products by SeaChem and other manufacturers and what I should be using. <It's a buyer's market... most of these products are very similar, read the ingredient labels.> Also, what is the difference between ionic and non ionic calcium in the reef aquarium. <Oh goodness, that requires pages... please read here: http://www.wetwebmedia.com/calcalkmar.htm > Thanks for the help and love your web help. Larry <Cheers, J -- >

Salty Setup.. >Bob or crew, First off, this is a wonderful site for aquarium enthusiasts. I will be setting up a 140 gallon tank with live rock and live sand. I have read on a website to place the live rock directly on the bottom first and then lay the sand. Is this your opinion? >>Yes. >Also, my tank will have an overflow that pulls water from the bottom as well as the top. Because of this, I have thought about an undergravel filter with reverse-flow power heads for the best possible bottom skimming and for oxygenating the sand creatures. If I do this, I will probably have only this undergravel water circulation in addition to the sump filtration circulation because I am getting close to the tolerance of a 15 amp circuit with the lighting, heating, pumps etc. What do you think of this idea? Thank you, Joseph Rouse >>Hhmm... well, I don't know that you really HAVE to worry about getting circulation through the sandbed, actually. Water movement is important, certainly, but unless you've got a huge amount of decorations or live rock blocking good flow, I wouldn't worry about going the reverse flow U/G. Hope this helps! Marina

- Circulation - I have recently purchased an Oceanic 72G RR bowfront. Seeing as the flow is inadequate on these tanks and I am not much of the do it yourself type, will 2 Turbelle Stream pumps on opposite sides of the tank be overkill for the various gobies, green Chromis, Oc. clown, and Yellow tang (will eventually become a reef tank)? I thought these looked like good products if the current is actually as gentle like they claim, but at 3175 gph each, it seems like it may be just too much by stirring up the DSB and possibly bothering the livestock. <The Turbelle Stream pumps are excellent products and do come in lower output models that 3,175 GPH - but as you note, an extreme amount of circulation in such a small box will likely slosh water out of the tank as well as disrupt your sand bed. The sand bed thing can be solved by putting a layer of larger, more coarse material on top to keep things settled, but it's my thinking that you can probably get away with three or four MaxiJet powerheads and get a good amount of circulation for this system without the cost of the Turbelles.> Thank you, Brian <Cheers, J -- >

- Marine Setup, Follow-up - Thanks again for that. The filter am going to run for the tank kicks out 1500 litres an hour (its a 40 gallon tank), will this be enough flow for the live rock as I do not want to add any extra power heads if possible.. Regards David <Quite likely you will have to add some extra flow source at some point - even though the tank is 40 gallons, one point source of circulation will create a laminar flow which will promote nuisance algaes as well as 'dead' areas where there is no flow at all. If you look at reefs, millions of gallons of water move through these every minute. There's no practical way to duplicate this in a fish tank except to say the more flow the better - fish and other livestock respond to it very well. Cheers, J -- >

Powerhead - 10/27/03 Is it safe to use a aqua-tech powerhead in a 46 gal. tank for water current? <Flow production is usually the primary use for powerheads. So unless there is something strange or peculiar about this brand of powerhead (couldn't find reference to Aqua-tech powerheads on the internet) it is likely fine for use in your aquarium as your flow production device. -Paul>

Internal Skimmer Box - 10/24/03 Anthony, <cheers> Just received you BoCP in the mail and it's an amazing wealth of information. Very redeeming to hear. Thanks kindly my friend> I do have one question regarding the internal skimmer box diagrammed on pg 42. How wide do you suggest making the area after the overflow wall? <just wide enough to comfortably fit your fist/hand in for cleaning, replacing/installing bulkheads, etc. Likely around 4" wide> I plan to have three 2" bulkheads to accommodate the ~2400GPH flow through the box in the 90G all glass tank down to the 30G sump. The system will utilize 1? return plumbing. How many return nozzles do you suggest? I was thinking 1 nozzle at each end of the tank. Or do you think there should be four. <at least four... and have you read my latest article on employing a closed loop manifold? (September Advanced Aquarist e-zine at reefs.org)> One at each corner with the current converging in the middle. Tank will primarily be SPS / Clam along with a few smaller fish <hmmm... more nozzles will be needed indeed to finesse the water flow. Size would be nice here> and some "reef safe" inverts. That is such a relative term isn't it? <very true!> Your thoughts are much respected and greatly appreciated. Once again you and the rest of the crew are doing a terrific job. Your hard work and dedication continue to improve this wonderful hobby. I know it has opened my eyes. Thanks yet again, Jeremy - Pineville, LA <your kudos are inspiring and just reward to us. In shared admiration... Anthony>

- Spinning Powerhead Attachment - Good Morning I have a questions about a powerhead attachment that I am trying to find. I have seen it on the web in pictures but I do not know what to call it. It looks like it attaches to your powerhead output, and it spins, while it spins it know has two output nozzles that spin around and circulate the water in two different directions. Do you have any ideas what it might be called or where I can find it. Thank You, Francis <Hmm... it's probably one of two things because for the life of me I can't think of anything that spins with nozzles that spin. You may be thinking of either a SCWD which attaches to a pump and has two outlets - the output of the pump will alternate between the two outlets - but they don't spin. The other possibility is a device who's name I've forgotten, but is basically a powerhead pivot - the entire powerhead is mounted to a rod that pivots on its axis, giving you a sweeping motion at the powerhead outlet. From those two, I'd pick the SCWD. Cheers, J -- >

Powerhead placement 10/13/03 Hey! I have read through the Marine Circulation pages, but am still leery bout my powerhead placement. <ahhh... OK> I have a 55 gallon FOWLR tank with a 2-3" sandbed and about 70 lbs of live rock. I basically put the live rock in the center of the tank - some of the pieces were so large that there is approximately 1" of clearance with the tank walls. <the sand is not deep enough and the distance off the wall is not very generous either IMO> Basic livestock is ~20 turbo & Trochus snails, ~15 red/blue legged hermits, 2 Oc. Clowns, 3 damsels, one Court Jester Goby, 2 Cleaner Skunk Shrimp. I have just added the beginner coral pak from Drs. F&S. I have a Amiracle sump rated for 150 gallon tank. Right now, I am using the CAP2200 that came with the sump and claims to be moving 495 gph. I also have a DolphinDP270 that moves about 100 gph. With losses, I figure I am moving about 475 gph. Your advice is to move about 10x, so I am a little shy. I have some Maxi 900 PH and a RedSea Wavemaster Pro that I would like to add. What is your suggestion on PH placement? Thanks, Paul <experiment until you find yourself producing random turbulent flow that leaves few if any dead spots in the tank for detritus accumulation. We have no way of telling you where that is re: rockscape and other outlet placement dynamics... a truly hands-on determination by you. Anthony>

Making Plans And Moving Water! Hello crew, <Scott F. your Crew member today!> Thanks, first off, for all you do. Great stuff. <Thanks for the "props"! We get a serious kick out of being here for our fellow fish geeks!> I just had a quick circulation question. I am constantly studying this hobby and am entrenched. <Scary how that happens! I can relate!> I am currently cycling a 90 gallon tank and am a new aquarist, so here goes my question. I acquired a great deal of marine equipment and am putting it all to use (love that eBay). I currently have about 2500 gph cycling through the tank, with 4 powerheads (300gph), 3 canister filters (350 gph) and a wet/dry (275 gph). I am planning a reef tank with a few reef fishes and was curious if the circulation is overkill. I have read 10-20 turns per hour is ideal, but I just wanted to make sure I am not hurting anything by going over that. <Well, when you take into account the volume of water that moves over a natural reef, there is virtually no way that we can over-do it in a closed system. Unless you have a decidedly laminar flow directed right on corals, blasting the tissue off of 'em, it's unlikely, IMO, that you could hurt anything. If properly applied, high water flow is always a good thing, IMO- particularly if SPS orals are in your future!> I am also planning on a protein skimmer in the future (maybe around Christmas when I get my first real fish, planning on a blue Volitans if I can find one) and at that time was planning on taking a canister or 2 off the main display. What are your thoughts? <In my opinion and experience- a quality protein skimmer is simply a necessity...I would not run a marine tank without one. Get the best model that you can afford...You won't regret this important investment...It will pay true dividends for years in the form of healthy animals and a more stable system...> Planning on a Volitans, perhaps an eel, and a tang along with corals. I also have about 10 hermits and snails. Not real sure on the corals yet, but am planning a reef tank around those type fishes. <A nice approach...Lots of good biological, mechanical, and chemical filtration is recommended...These animals give of a lot of metabolic waste, and corals require high quality water conditions. sometimes, a tough balance to achieve..> Studying up to one day house a seahorse tank. If I can learn enough and do it the right way. Don't want to bring any into my house and kill it. <Awesome attitude...You'll go far with this philosophy!> Thanks again for all your help and keep up the good work. Tom Hall <Best of luck to you, Tom! Regards, Scott F.>

Water Movement 10/-3/03 I read the article on how to have proper water movement, but I'm unsure if my setup will do the job. I have a 50 gal.(36 x 15 x 20) aquarium with an AquaClear 300, and two Eheim powerheads, each pushing 176 gph. I have a 652 gph of total water movement, but the placement is my concern. I have the AquaClear in the left-middle on top. One powerhead is in the upper left hand corner pushing to the lower right, and I have the other powerhead in the lower-right, pushing straight back to the other powerhead. I think the AquaClear 300 is pushing too much water for the powerhead next to is for it to have any effect. Should I move it lower? I just want to make sure I do this right, since it's very important once I have my corals involved in the picture. You guys are all awesome! Thank you in advance! <I wish I could help you, mate... but we have no way of answering this question. Pump placement is not about a standardized local (upper left, forward right, etc)... it is entirely case by case as influence by the individual rockscape you have designed. You simply need to adjust all such devices until you get a convergence that creates random turbulent water flow in the tank with few spots for detritus to accumulate. Very much and eyeball adjustment process. Best regards, Anthony>

Moving Water (Flow Questions) I have a big mess of questions for you today. It's late, so I'm sorry if some of this doesn't make total sense to you! <You'd be surprised what does make sense to me these days!> All of your help and time is appreciated! <As is your participation and sharing! Ask away!> I have a 75 gallon saltwater aquarium and I plan on adding corals soon. I have a Tide Pool II for a filter along with a AquaC Remora skimmer. I am using a SOS overflow. Right now I am using a Rio 2500 for my return pump. This is giving me about 540 GPH on my return (as far as I know anyway). I want to add enough water current in my tank for the corals. Should I just buy 4 larger power heads and use them to make water motion in my tank, or should I buy an Iwaki MD30RLXT that does about 960 GPH and use it as my return pump. I have an extra SOS overflow so I am good up to 1200 GPH if needed. <That could work. Or, for more simplicity, you could employ external pumps, such as Geminis (they move 960 gallons per hour at like 15 watts!) or Tunze Stream pumps (if you don't mind spending a few $$$). Both can get you up to "warp speed" (okay- SPS water flow conditions) quickly!> If I used the Iwaki as my return pump I would split off the return into different spots to make my water motion. <Or, you could connect them to rotating returns, such as Sea Swirls, which I love!> If you think I would be better off with power heads, how many and how many GPH should each one move? <I'd look into the Geminis or Tunzes, as outlined above- they can move from 960 GPH to near 2300gph (Tunze)...They do a JOB!> On to the second part. I also have a 29 gallon saltwater aquarium that is tied into a 10 gallon aquarium. The 10 gallon is going to house a mini reef. They both flow into a 10 gallon sump that I made. I use a AquaC Remora on this tank as well. I haven't added any corals to this setup. The return pump is a Rio 1400 and a Maxijet 1200 (the Maxijet runs through my UV). My question is this, how many GPH should go to the 10 gallon and how many to the 29 gallon tank? <Well- that's gonna take some trial and error. In SPS tanks, we shoot for 20 plus turns an hour. It's not a bad goal to shoot for in a fish tank, either, IMO!> Again, am I better off with a bigger pump that moves the water in different spots of my tanks, or am I better off with separate power heads. <I think on this smaller system, I'd go with one bigger pump that you can tee off or redirect as needed. Less obtrusive hardware in the tank, less electrical hookups, less heat (important in a smaller tank), and less hassle, IMO!> I will only be adding corals to the 10 gallon. If I am better off with power heads, how many and how many GPH? <As above...Take your pick!> One last thing. I hate to bother you guys because I know how swamped you all are. <It's not a bother- that' why we do this! We love this stuff!> So again, thanks for all your time and help. I do read through the FAQ, but I have been unable to find the exact answers to my questions. So here's my last question and I'll be on my merry way. For my 10 gallon mini reef that I am going to start, I bought a CustomSeaLife PowerCompact/Moon-Lite Fixture that has one 40W 10,000K Ultra Daylight bulb, one 40W Actinic Blue bulb, and one Moon-Lite. I figure this light will be good enough for most corals, do you agree? <In a shallow tank, it can probably suffice. You will undoubtedly have some rockwork on which your corals will be placed, so I'm sure they will be within a few inches of the light source? You can always help compensate for less light (if this is the case- and I don't think that it will be...)by feeding more...A tradeoff. Experiment with some hardy SPS frags and see how they do under this lighting regimen...> Any input would be great. Love the website, keep up the great work! Steve <Our pleasure, Steve! Thanks for the kind words! I think that you're gonna have lots of fun working on these systems! Let us know how it turns out! Regards, Scott F>

Skimmer flow Bob- could you tell me if a protein skimmer water movement adds to the flow rate of the reef tank. The skimmer is out side the sump with a external pump 700 gph. RGibson <I'd say yes... and would like to add a proviso... that there is MUCH more flow in the wild in most all settings than anything a hobbyist supplies... Practically speaking, w/o sucking up or blasting your livestock against a tank wall, there is no such thing as "too much" water flow. Bob Fenner>

Use of an airstone Hi, Have a reef tank with anemones, paint brushes, crabs, shrimp, and misc. reef safe fish 125 gal. Was wondering if I can use an air stone that makes the mini-bubbles approx. 12 " long along the rear bottom of tank, figured it would look nice, add some air to tank, but was wondering if it would hurt anemones ( have no corals), and if there are any pros and cons of same. Thanks in advance. Louie <Should be fine. One of my fave applications as a matter of fact. Placing one of these along the inside end of an aquarium really moves the water... in a complete gyre. Bob Fenner>

- Shaken not Stirred, Follow-up - Thanks for such a quick response. <My pleasure.> I will give it time. I'm glad to hear you say that the ESV is to your liking as I like to be consistent. I do have one other quick matter in which your opinion would be much appreciated. I was wondering if perhaps my bio load is excessive. <It's on the edge - I wouldn't add anything else.> In the afore mentioned tank I house a grown Clarks clown, medium yellow tang, blue damsel, 2 fire gobies, 1 Atlantic spotted hawk, a purple pseudo, and a banded goby along with a handful of peppermint shrimp. As I mentioned before, I have about 110 pounds of rock, a 20 gallon sump half full, run a quiet one recirculator, and have a Red Sea Berlin classic on a Rio 2500. I also use a Rio 1100 and 2 Rio 150's to move water. <Sounds pretty good, although you could probably do better with two powerheads larger than the Rio 150's - perhaps some MaxiJet 1200s - robust circulation will be the trick to keeping this tank on the up and up.> Thanks again for your insight. <Cheers, J -- >

Water Flow Is the water flow from the sump to the skimmer and back is this part of the over all flow rate for a reef tank. RGibson

Overflow question 9/12/03 Gents. , how's it going? <Well... hoping the same for you too :) > Here's my question, I have a 90 gal. reef ready , I want to get more flow for the tank, <yes... a common problem with mi-marketed and so-called "reef-ready" aquariums which simply do not have enough holes drilled for adequate flow> I currently have a mag 9 and 3 power heads on it. I would like to get rid of the power heads and put on another external overflow box and then a second pump. My pre-drilled overflow right now is almost maxed out I would believe, <correct> so I was wondering if I can a second external overflow box and then maybe then just run a single larger pump, I would tee off the outlet lines and have one go into the pre-drilled return and have the other come in at the opposite end and hang over into the tank. What do you think of that? Is there a problem with it? <very good... and assuming that you will have the tank drained and drilled for extra holes to handle the larger pump. However, if the second overflow is going to be a over-the-top siphon, I would not recommend it as they are unreliable in the long run. Always best to drill larger/extra holes.> Is there an easier way to get more flow that I don't know about WITHOUT drilling more holes for a closed loop? <nothing foolproof - without drilling, you have the inevitable risk of broken siphons and serious floods or pumps burning out> Please let me know , I have all LPS corals, and I know they don't like a lot of flow, but I do think I need more, if I'm going to take out the powerheads that is (I would like to reduce some heat) thanks <we have quite a few articles archived here on wetwebmedia.com regarding water flow... do browse. Anthony>

Overflow Question 9/9/03 Greetings Crew, <howdy> I've got a question regarding an overflow box on my soon-to-be sps reef tank (150gal). I've read in Anthony's coral fragging book that one can increase the efficiency of the protein skimmer by overflowing the thinnest layer of water possible. <yeppers> To this end, I was thinking of adding to the back of the tank an external overflow box that would run it's entire length and drilling 3/8" holes equally spaced across in the tank back. The external box would house three 1 1/2" stand pipes. Is this structurally sound and will this provide adequate flow for the 20+ turnover rate I'm hoping to achieve? Thanks, Ron <it is likely to be structurally sound or stronger for the panes of glass from the overflow acting as braces. I must admit though, my reference was to holes drilled high on the back wall... not the bottom of the aquarium which I avoid (noisy and wastes space). As to the flow rate... do check the bulkhead mfg specs for reassurance - some variation here. Best regards, Anthony>

Closed Loop Flow Rate - 8/18/03 Ok guys, Oops.. and gals. <that will cost you extra... I don't wear a Bo Peep outfit for nothing> Quick question with a quick simple answer. <OK> Is a 1 1/2" bulk head for the in and out of a closed loop flow system large enough for approx 900gph? <yes> Or would you recommend 2"? <no> Now see? <yes> That was painless wasn't it? <yes> Once again thank you all for your time and dedication to this wonderful hobby. <welcome> I'm sure we'll be talking again soon. Jeremy <my pleasure. Anthony>

Closed Loop Flow Rate - 08/18/03 Thanks for the quick reply Anthony. <always welcome> The closed loop intake and return were going to be put directly behind the live rock to keep debris from settling, <not necessary if the rockwork is built properly (minimum 4" away from the/any wall). But OK...> but I suppose if I had enough turbulent circulation this wouldn't be an issue and I could save the money on the second pump. <correcto> I knew there was a reason I kept ya around. <danke> If I were to just use a larger return pump, how many returns would you split it into and where would you have them enter back into the tank? <it's funny you should mention this... I am just finishing an article with a nice 3-D drawing of a return manifold! Do check back in days to see if its posted yet :) To answer your question though, do a keyword google search of our site for "teed manifold". More than a few great FAQs on this issue > I was going to have to in the front corners, but now I suppose I could add 1 to the back as well. <even more needed likely... 4-6 minimum, and each with a swiveling elbow or adjustable flex (interlocking) pipe> Was thinking of a Mag 24 but I read they aren't recommended for external use. Don't really want the extra heat in my sump. <Hmmm... is it really an issue? Are you borderline with high temps? Else it is a good pump for cheap> My other choice would be a Dolphin Aqua-Sea amp master 2700 or 3000. <have heard good and bad (seals/inaccurate claims of low power consumption) on this brand FWIW. I'm still saying IWAKI if you don't sneak away with a mag drive> Or should I go larger given the bends in the return plumbing? Was looking for 15-20x turnover for a 90G reef. <very good> Over flow box with two drains 1 1/2" or 2" bulkheads for 1800-2500gph? Neither will handle that kind of flow... at least not quietly ;) You need more holes or larger holes. Do consider my internal overflow idea mentioned in my "Book of Coral Propagation" (Calfo 2001)... discussion/excerpts of it also in the archives of wetwebmedia.com (use a honed keyword search). kind regards, Anthony>

-How much flow is enough?- Would you consider this water flow good enough for my 90 gallon tank: I have 270gph oscillating powerhead directed from left to right on the tank. BakPak in the middle (flow going toward the front) and flow from Fluval 404 directed towards right aquarium wall (so the current is 'broken up' by the wall). Is that good enough? Thanks <If this is to be a reef tank, you would probably want to add another +/- 300gph powerhead or two. A good way to see the current is to watch where the food goes when you feed. Use powerheads to keep water moving through the rocks and to eliminate dead spots. Check out http://www.wetwebmedia.com/circmarart.htm for more info. Good luck! -Kevin>

-What to do with the excess flow...- If I stuck with the AMP Master 3000 could I tee it off to feed flow to a refugium? <Yep, and have it drain right back into the sump.> What kind of flow should you have for a refugium? <Well, that would depend on what you're trying to grow in there. For most purposes, you'll want very slow flow, maybe only 2 tank turnovers an hour. Good luck! -Kevin> Regards, D'Wayne

- Water Flow, UV, and Plumbing - Hey! <Hello to you.> I need to increase the turnover in my tank and increase the efficiency of my UV. I have a 75g FOWLR, with built in overflow that goes down to a wet dry, in the wet dry (sump) I have the skimmer. I have a little giant pump rated at 590 gph w/ a 6' head, that also pushes water through a UV that is rated at 350 max outflow, the pump is connected to one end of the sump. What I figured is that I do not have enough turn over in my tank and that the flow is too strong for the UV to be effective. So what I want to do is to get another external pump rated at about 400gph including the 4-6' head to pull water out of the sump and connect this pump to the UV, my tank has one main hose that Tees off into two bulkheads, one on each of the corner of the tank, (the main is a 3/4" hose). 1. The only way that I can get this other pump to pull water from the sump is to have a hose or PVC tube and elbow go over the sump from the outside and down in the sump to pull water, my sump is about 14" high, then connect this one to the UV, would this work? <Only if you have a pump that can self-prime... and I can't think of any in that GPH range. Most pumps won't 'suck' water from any height and instead rely on being primed by gravity - via the bulkheads on the side of the sump.> I can't really drill another hole in the sump. Is there any other way of doing this? 2. To get the water back in the tank I thought of joining the end tubes (one hose coming out of the outlet of one pump, and the other one after the UV from the other pump) into a Tee that will be connected to the main and then this will Tee into the two hoses that go to the bulk heads. Basically combining the outflows of two pumps (pushing up) into one main going up to the tank. This is the easiest option for me. <It's not the best option, however... better to have each flow into the tank individually.> The other option (but it's harder to get to) is to have each of the pumps connected to each of the bulkheads, through their own hose, no Tee. This will have different flows out of each bulkhead, I don't this is a problem, is it? <It's not a 'problem' per se, and it's preferable to combining both pumps to one.> Would this increase my turnover? <Yes, but you might want to examine your UV to see if moving water through it at its highest rated flow is in your best interest. For example, a 25 watt UV might be able to move 400 GPH of water through it, but if you want to kill protozoans [which is what I'm guessing you want to do] with the UV you need the water to sit in front of the bulb a little longer, which [again on a 25 watt bulb] means slowing the flow down to 150 GPH.> Any other suggestions? <Cheers, J -- >

Food dye Ok, I'm going to take a chance and ask what may be considered a dumb question (if there is such a thing). Is it ok to use food dye in a tank with no livestock (except LS/LR) to see how the water flow is in my 90 gallon tank? I'm thinking this might help me better position powerheads and inflows. <Yes, safe... and a good idea. Have seen such use in limnology classes, demonstrations in relation to thermoclines, other phenomena in aquariums> Thanks so much for the great website and books. Mark <Thank you for your kind, encouraging words. Bob Fenner>

Circulation 7/22/03 Pardon my ignorance and allow one more question on the subject. You mention a closed loop as method of increasing flow. I take that to mean that water is pumped straight back to the display tank without passing through sump, skimmer, etc., is that correct? <correct. It is independent of the drains (and their limitations) by tapping the display and returning water directly to it... thus sparing the need for unsightly internal powerheads> If so, other than aesthetics, how is that different from running power heads in the tank? <the pump is external, more energy efficient, imparts less heat to the water, they are longer lived, produce more volume/water flow per dollar spent, etc> The total flow of return pumps and power heads as they are now is about 2,800GPH or a 16X/hr exchange. <nicely in the ballpark> If I wind up with a couple of Tunze Streams and max out flow through sump, the total flow would increase to 7,500GPH for a 42X/hr exchange. In other words, is 1,500GPH through the sump/refugium plus 6,000GPH internal recirc with Streams (can't believe that they move that much water but that's what the specs say) in a 175-gallon tank going to allow me to eventually keep clams and SPS corals? Many thanks, George. <correctly diffused/distributed... you will easily be able to keep and grow sps corals and other high flow reef invertebrates. Best regards, Anthony>

-Increasing flow- Well, you have answered 2 times and that has been some of the best advice I have got. So I must continue for the life of my inhabitants. <Glad to help, Kevin here again> Fish only set up. I have a 75 gal, overflow, with a Wet Dry filter underneath, the one with bioballs, and then I have a G1 skimmer (Euroreef knock off) in the other half of the "sump". Then I have a Little Giant pump sucking it out @ about 590gph (with a 6' head), going through a UV and Ting off into two nozzles (on each top corner of the tank) and back in the tank. Well, first the UV is rated at 350gph and per what I read the flow is a big deal for UV, so that pump is too fast for the UV, right? <Not only is it too fast but the UV will add lots of head pressure to the pump resulting in way less then 590 @ 6'>And second I believe the pump @590gph is only turning it over a little less than 8 times, and I thing it could use a bit more, right? <If you were truly getting almost 590 @6' then you'd be in good shape, I doubt this is the case w/ the UV> So what I want to do is to get a pump rated @350 or so to pull water from the sump in to the UV and then "join" the flow back up to the tank from the other pump, on the same hose of the first pump, this is one option and the easiest for my set-up. <Use separate hoses, don't connect the two pumps> The other option will be to have a hose for each pump and each one into it's own nozzle, one weaker in flow than the other one. Which one would work better/be more efficient? <Separate hoses, although you can still T off the main> Would this increase the flow? i.e. 590+350gph? <It would definitely increase the flow. You will get some added flow from the UV (keep in mind that running a pump rated 350 back to the main thru the UV must be able to handle both the head pressure from going all the way up to the tank as well as the UV. That said, to do that you'll need a pump rated much higher. Your best bet would be to use a pump rated 350 or so @ 0' and have it pour back into the sump after the UV.) You will also get much better flow from your main pump, make sure your overflow can handle this!> Once again thank you, thank you. <You're very welcome! -Kevin>

Water Flow Hi folks! Greatly appreciate some advice please. I have a 6-month old 12G reef aquarium idiotically stuffed with perhaps a bit too much live rock on top of a live 4" DSB. A 12G reef tank should do fine with approx 120 to 240GPH water flow but for all the rock. The built-in pump/filter provides 150GPH, but even after adding a 112GPH powerhead the water flow was inadequate and another 112GPH powerhead was added in an attempt to stop slime-algae growth. <slime algae growth can be a sign of an excess of nutrients like Phosphate (especially organic phosphate) in the water. Lack of nutrients are what keep its growth in a health system, limited> Both are in opposite upper rear corners with cross-currents in upper front of aquarium in an attempt to reduce laminar flow. <Studies have shown that chaotic flow, rather than laminar flow, actually encourages algae growth. Also, laminar flow (high flow, not high velocity) is what is present on most coral reefs> Still had slime algae problems despite moving powerheads all over the place. I cut back lights from 12 to 8 hours, started hand-skimming, stopped feeding the corals, moved most snails and crabs elsewhere and somehow got rid of the slime algae. So, to celebrate, I added two 4-month old Perculas from a local breeder and found that they couldn't swim with 374GPH without looking like they were about to be blasted into the aquarium walls. I shut off the powerheads to lessen acclimation stress and am hoping that with feeding the fish and the lesser water flow, that I'm not going back to slime-algae producing. <The increased bioload from the clownfish will produce nutrients that will help fuel the algae> Before getting the Perculas, I was using sand blowing and coral movement as a guide to how much water flow and powerhead placement. All my soft corals are doing great. Now I am using the fish as a guide. I know these guys are poor swimmers, but I still feel that I need more that 150GPH because of all the rock, even though I can now see the xenia pulsing nicely whereas before they would blow wildly (still growing like weeds, though). Since I am shortly adding a 15G sump under the aquarium, I am trying to figure out what size external (trying to lessen heat exchange) sump pump I need. My skimmer for the sump is a Tunze Comline 3110/2. Since it doesn't need a pump, I believe I'll only have to account for maybe 6 to 8 elbows (two returns from T off SCWD right after pump), about a 4 to 5 foot head for the slanted drop from overflow to sump via flex tubing and the SCWD and flare nozzles. Pre-fish, I was thinking of an IWAKI at 420GPH, figuring that maybe after flow losses, I'd get about what I currently max out at - 374GPH. But now, with no slime algae, and with the fish, I'm up for suggestions for the quietest pump over 150GPH (and under $150) that will allow the Perculas to still move. An Eheim 1048 is 160GPH, hardly more than what I have now, and a 1250 is 320GPH. Baring other suggestions, if I have to throttle back either an Iwaki or the Eheim 1250, which would be quieter and/or better? <personally, I am a fan of the Iwaki line of pumps. I have used them for a while now on outdoor and indoor lab and culture systems; perhaps try distributing the flow from the pump returns more widely to get a more flow/less velocity (velocity is what your clownfish seem to be having trouble managing, yes?)...> Thanks for your patience, humor, thoughts, time..... Brent, the Anal-Retentive Micro Reef Manager (copyright 2003) <best, Chris>