BGA linked to small hair in water column? 10/29/11
Aloha,
<And you>
Thank you for all that is Wet Web Media. I just finished reading most of the FAQ's on BGA and am working on correcting the mess that is all over this acrylic 210 gallon FOT that I just got put in charge of. The tank is currently being dosed with .23ppm Cu+ indefinitely (something I plan to get rid of) as well. This is certainly not helping with the Cyano and I actually think it was one of the biggest factors for this explosion.
<A possibility>
The other day as I was staring into the water column of my tank I noticed a ton of little tiny hairs (~1-4mm) floating around in the water. I was wondering if this has anything to do with the Cyano in my tank or if it was something you have heard of before?
<Have seen such in systems; not often related to BGA>
Unfortunately anytime you mention the word "hair" in any aquarium or marine type search you get bombarded by hair algae results and no mention of it actually suspended in the water column.
Thank you very much for your time
Erik
<Easy enough to look at through a microscope... Cyanobacteria threads are definitive... Bob Fenner>

Re: BGA linked to small hair in water column? 10/30/11
Aloha Bob and Crew
Thanks for taking a look at these. The "unknown" named picture (400x) is the structure that I believe to see floating in my water column.
<Thank you for this... does appear to be some type of Cyano to me>
It is the only thing of size within the sample that I took. Most of the similar structures are smaller and do not branch as much. I also scraped a bit of Cyano and took another picture (all by using my cell phone and scope).
Any idea what this could be as it doesn't look like Cyano to me?
<I do think this is BGA and that it is modifying the environment (poisoning other life) to advance it's own extension in time and space... You need to do "something drastic" to "re-set" the dynamics here... to favour other photosynthates (perhaps add a bunch of another, desirable species). BobF>
Mahalo
Erik

Algae Battle Since Sept 19th 10/16/11
Hi Guys,
<Kev>
I've spend lots of time on your site researching a rampant algae outbreak in my tank. I'm firmly entrenched fighting a battle against what I think is red cyanobacteria. (Rust colored mat covering rocks with bubbles in higher areas of tank. Brown strings coming off rocks in some areas recently).
<I do agree>
I've had this problem since September 19th. Since then, I have been doing 25% water changes every other day, scrubbing the rocks with the end of my siphon hose to remove as much of the red stuff as possible each time. The following day the stuff is back, and my vicious cycle of making water and changing it continues.
I think I've done everything you guys have suggested in previous posts to get rid of this stuff. The only thing I have not done yet is shut the lights off, only because I am concerned for the survival of the inverts. I have a quarantine tank set up, 12g JBJ Nano, but I think the lighting in insufficient for the clams. (2x 24w. 10000K and 2x 24w. actinic fluorescent). LFS suggested that I use Ultra Life Red Slime Remover, but I have not used it because I prefer to use natural methods of correction rather than adding chemicals.
<Am not a fan of chemical algicides>
Since I set up my tank in 2009 I always purchased RO water from my LFS with no issues. I recently purchased a TDS meter to test the water from the LFS and found that they were selling me RO water with TDS of 120+ppm.
<Uhh, this is NOT RO>
I decided to install a SpectraPure Maxcap 90 gpd RO/DI system in August for my home so I could be sure of the water quality. My RO/DI system produces nice "clean" water with 0 TDS, confirmed by an in-line TDS meter as well as cross-checking with my handheld TDS meter.
I usually don¹t have any problems with the tank. I have had a few patches of diatom that cleared up on their own, and a minimal amount of flatworms that I siphon off as I see them, but usually I don¹t have any algae on the rocks at all. The only correlation I can see is that this problem started right after I switched to the "clean" RO/DI water. Is this just a cycle that will resolve itself as the tank is (still) getting used to the new water?
<Might>
If I continue my obsessive water changes will there ever be any relief?
<I'd look into placing a good-sized DSB here, possibly measure RedOx... utilize ozone>
Are my frequent water changes just prolonging the problem? Have I misdiagnosed the problem? I'm very frustrated at this point.
<Understandably so. Do search WWM re these tools>
Thanks for any advice you can give.
Kevin
66 gallon Res Sea Max 250, (3x T5 actinic, 3x T5 10,000K lights, protein skimmer, Chemipure carbon,) 85 lb. live rock
2 clownfish, purple tang, hippo tang, cardinal fish, aurora goby, assorted snails and crabs (all in tank for 1+years; healthy)
Brain coral, bubble tipped anemone, assorted mushrooms, 2 sun corals, torch coral, crocea clam, derasa clam, maxima clam (all in tank for 1+years; healthy and growing)
Feeding since Sept. 19th: Monday: frozen food (only what is consumed in a few minutes), Tuesday: nothing, Wednesday: clip marine algae (what is not eaten in a few hours is removed, large floating chunks removed), Thursday: nothing, Friday: frozen food, and the pattern continues anemone fed every 4 days with small piece of shrimp, sun corals are removed from tank for feeding with mysis every 4 days
Water changes pre-problem: 25% every week
Current parameters:
Ammonia, Nitrate, Nitrite, Phosphates - 0
Alkalinity ­ 7dKH
Calcium ­ 320
<A little low... Magnesium?>
pH ­ 8.2
Silicates - 0
Salinity 1.025 (Instant Ocean Reef Crystals)
Temperature: 78
Lights on 11 hours/day
<Bob Fenner>

Undying Algae, BGA 6/5/2011 /RMF
Hey Guys,
<Marc>
Second time writing in, last time was about 4 years ago. Your support and recommendations were great then, hence why I'm coming to you again!
I've had a 90g tank (20g sump) setup for about 2 years now. Recently its gone through lots of changes as I just couldn't get my nitrates/phosphates down to reasonable levels. I removed all my bio-balls in the overflow, and removed two large chambers of crushed rock in my sump. This improved things greatly, but parameters were still way out of whack. I then removed lots of rock (I realize now I had way too much) and re-positioned everything for much better flow through the structures.
<Good moves>
I've also been using the vodka method for 3-4 months now with fantastic results. After finishing all this re-work over the past few months, my parameters are as follow:
Temp: 26 C
Salinity: 1.025
Ph: 8.3
Alkalinity: 10 dKH
Calcium: 500
<Too high... see WWM re>
Ammonia: 0
Nitrite: 0
Nitrate: 0
Phosphate: 0
<... NO NO3, HPO4?>
The tank is 24" deep and running 2 x 250w MH (14k) for 10hrs a day. Tanks isn't too far from a window, so it does get some subsidiary light in the morning before the halides turn-on. Not too much though. The substrate is about 3" deep. I have about 40+ times water flow. Sump pump is 5,000L and 13,000L total output in display. All water comes through a RO filter.
Skimmer running 24/7.
On to the problem, about 6 months ago; Cyano (I think)
<I do too>
was introduced into the tank.
<Is omnipresent...>
The whole tank was regularly covered in it in short time. I was siphoning and scrubbing my rocks to keep it clean weekly. At the time I wasn't too surprised as the parameters were all out of whack. However, I have now got everything in pretty good condition, yet I still have this same algae growth. It appears different now (in fact, before I started making all my changes) and is perhaps 2 different types of algae. I'm just totally at a loss now at what to do and what I have growing in my tank.
<Read here: http://www.wetwebmedia.com/bluegralgae.htm
and the linked files above re BGA, control>
There appears to be a purplish film on the glass, which wipes off with no problem. However, there's also a browner/redder algae growing on the rocks.
This is the stuff that takes over the tank...I'm not sure what either is.
<... requires microscopic examination to be sure, but these are all likely BGA>
My guesses were towards Cyano, diatoms (except they never seem to cycle out) and Dinoflagellates. I've attached some pics which show the brown and purple growths, please let me know your thoughts.
Regards,
Marc Steeb
<Write back after reading if you have further questions. Bob Fenner>
Undying Algae/Algae Control/Vodka Dosing 6/5/2011 /JamesG
Hey Guys,
<Marc>
Second time writing in, last time was about 4 years ago. Your support and recommendations were great then, hence why I'm coming to you again!
<Great!>
I've had a 90g tank (20g sump) setup for about 2 years now. Recently its gone through lots of changes as I just couldn't get my nitrates/phosphates down to reasonable levels. I removed all my bio-balls in the overflow, and removed two large chambers of crushed rock in my sump. This improved things greatly, but parameters were still way out of whack. I then removed lots of rock (I realize now I had way too much) and re-positioned everything for much better flow through the structures. I've also been using the vodka method for 3-4 months now with fantastic results. After finishing all this re-work over the past few months, my parameters are as follow:
Temp: 26 C
Salinity: 1.025
Ph: 8.3
Alkalinity: 10 dKH
<I shoot for 7dKH.>
Calcium: 500
<Too high, dKH problem lie ahead maintaining this level.>
Ammonia: 0
Nitrite: 0
Nitrate: 0
Phosphate: 0
<Where is you magnesium at?>
The tank is 24" deep and running 2 x 250w MH (14k) for 10hrs a day. Tanks isn't too far from a window, so it does get some subsidiary light in the morning before the halides turn-on. Not too much though. The substrate is about 3" deep. I have about 40+ times water flow. Sump pump is 5,000L and 13,000L total output in display. All water comes through a RO filter.
Skimmer running 24/7.
On to the problem, about 6 months ago; Cyano (I think) was introduced into the tank. The whole tank was regularly covered in it in short time. I was siphoning and scrubbing my rocks to keep it clean weekly. At the time I wasn't too surprised as the parameters were all out of whack. However, I have now got everything in pretty good condition, yet I still have this same algae growth. It appears different now (in fact, before I started making all my changes) and is perhaps 2 different types of algae. I'm just totally at a loss now at what to do and what I have growing in my tank.
There appears to be a purplish film on the glass, which wipes off with no problem. However, there's also a browner/redder algae growing on the rocks.
This is the stuff that takes over the tank...I'm not sure what either is.
My guesses were towards Cyano, diatoms (except they never seem to cycle out) and Dinoflagellates. I've attached some pics which show the brown and purple growths, please let me know your thoughts.
<I'm thinking this may be due to your vodka dosing and is/can be a downside with this method of dosing. Problem with dosing vodka is the rapid production of bacteria within the entire system which in turn feeds algae.
Dry vodka dosing via carbon polymer pellets is a much more desirable method as the bacteria are limited to one area, the reactor. The output from a reactor that is used for dry dosing can be directed toward the skimmer's intake pump which will reduce the surplus bacteria a good deal. Two Little Fishies (Julian Sprung) has a nice inexpensive reactor (35.00) that works very well with the carbon pellets.>
Regards,
<Ditto. James (Salty Dog)>
Marc Steeb

re: Undying Algae, BGA id f', now control 6/5/2011
Thanks for the reply, confirms what I suspect. I'm still a little confused on how to treat this though. I read through the article you recommended and it seems to focus around manual removal and filtration.
<... keep reading... competition, predation... preventative means of nutrient limitation>
If get down to it the recommendation is to control nutrients better. I always thought DOC's and nitrates/phosphates (nutrients) were essentially one in the same.
<One set includes the other, but not vice versa>
Get your nitrates/phosphates down to undetectable and you have little DOC's in the water...?
<The universe is more dynamic... it may well be that the BGA is/are taking up these readily>
With my current testing, nitrate/phosphate are at 0 ... so unless I'm wrong (wouldn't surprise me) DOC's should not be present.
<Guess again>
If I'm wrong, than DOC's need to be removed via another method ... skimming? My current skimmer's performance is rather erratic, to say the least. Perhaps time to upgrade.
<Maybe>
I received a reply from James (Salty Dog) on the previous email in which he proposed the vodka dosing was causing the problem due to overgrowth of bacteria.
<Can>
My vodka dosing has trailed off to a maintenance regime now and definitely has a large part to do with my low nitrates/phosphates. Do you think I should change something with the vodka?
<I suggest you read re on WWM. I would NOT continually use>
Thanks again!
<Welcome. BobF>
Regards,
Marc Steeb

The Red Demon "Cyano" HELP/Cyano Control 5/5/2011
Hello WWM Crew,
<Hello Brian>
I know you probably heard this about a million times before,
<Not quite that many.>
so I am going to make it a million and one. Thanks so much to all the people of WWM who share their expertise, experience, knowledge and most of all their free time to help everybody in this hobby, and do it just for the love of the hobby.
<You're welcome.>
I stumbled on this site 3 yrs ago by accident and have been reading almost everyday since then. This will be my first question that I am asking and I know you've dealt with this question over and over again and I have read, and read, and then did some more reading on this problem and have adjusted and changed everything that causes red Cyano. I am hoping that if I give you a rundown of all my equipment and husbandry and livestock you will be able to spot something that I am missing. My LFS guy says that I am overstocked and the low oxygen is fueling the Red Cyano. I disagree with him simply because I had basically the same fish in a tank 1/4 the size I have now with not nearly as much equipment and husbandry (since I've been reading FAQ on your site) and I had no problem with Cyano then.
<Low oxygen is one cause of Cyano and this can be due to stagnant areas in your tank. Properly positioned powerheads and the use of a Wavemaker generally eliminates these areas.>
My other LFS guy says that my skimmer is too small for my tank and I should have a stronger one.
<Nutrients are another cause of Cyano and a good efficient skimmer can go a long way in helping to control Cyano.>
I found a used Tunze 9010 on line for a good price so I picked this one up and installed it in my sump. I know the Tunze I bought is working as the guy I bought it from had it in his sump and there was a lot of skimmate from his 180gal. I don't understand the sizing of skimmers. If for example your skimmer is not properly sized shouldn't it be pulling a lot of skimmate out to it's capacity and if the bioload is too heavy it just doesn't pull out anything over the capacity of the skimmer?
<Any size skimmer will pull out dissolved nutrients, what is important in skimmer selection is how much water the skimmer processes per hour, contact time, and size of the bubbles. There are skimmers out there rated for x amount of gallons that actually perform inefficiently when used in their rated tank size. My opinion, bigger is better. I use a skimmer rated for over twice the size of my tank.>
I guess I will start with my equipment.
90gal tank
100lbs Fiji LR
120lbs Caribsea LS
20gal sump
CPR CS102 overflow (I know, the next one will be drilled)
In100 Vertex skimmer (which doesn't seem to produce skimmate the way people talk on your site. I think this might be my problem or I don't have much to skim.)
<I've used this same model for two years and felt it performed very well.
Did you clean the cup/riser tube at least once weekly?>
The Tunze seems to pull out more than the Vertex In100.
<It may be because the Tunze 9010 processes a little over 300gph and is rated for tank sizes up to 260 gallons where the IN100 is rated for tanks up to 100 gallons. You should see some improvement with the use of the Tunze but do not expect overnight results.>
CPR large HOB fuge (5gal) with Chaeto and reverse 12hr lighting cycle
<Refugiums are a plus in controlling Cyano but a five gallon fuge is a little too small for your size tank to have any significant impact on nutrient control.>
Mag 9 return pump
3 x Koralia #4
2 x Koralia #1
1 x Maxi jet 1200
<Mmm, should have plenty of flow here.>
PC lighting 2x65w 10,000k 2x65w 50/50 10,000k/actinic 12hr cycle (just put new ones in March, 26, 2011)
1 x 48" Coralife T5 strip light 2x28w 10,000k 12hr cycle (just put new ones in March,26, 2011)
System flows from overflow to sumps first compartment with only filter floss to catch debris.
<Is the floss replaced weekly?>
From there 2 baffles then to the second compartment which has the Vertex skimmer(now the Tunze) and the intake powerhead for the HOB fuge with a venturi hooked up to the powerhead for oxygen to the HOB fuge. From there 2 more baffles which has a Polyfilter, Purigen, and Phosguard in between baffles and then more poly wool. To the last compartment which has the Mag 9 return pump and the return flow from the HOB fuge. In the tank the Mag 9 return flows from the back corner to the front opposite corner.
<If your sump permits, I'd put the skimmer in the first compartment and the floss in the second.>
The Koralia #4 are on each side of the tank facing the front center glass.
The Maxi jet 1200 is on the back glass at the bottom with a T on the output sending current along the back bottom of the tank. The two Koralia #1 are on the back glass at the bottom corners sending current to the front glass along the sides. The third Koralia #4 right now is on the front glass in the center pointing right at the LR.
My husbandry goes something like this. Once a week I vacuum the sand and clean the glass. I use only Tropic Marin Pro Reef salt. I use a 5 stage ro/di filter with a tds reading of 0. I aerate my ro/di water for 48hrs before salting and add Seachem Marine Buffer. My newly mixed salt water aerates with a Maxi jet 1200 and a heater 24/7 and I aerate for at least 7 days before a water change. Also my DIY auto top off ro/di water is buffered, heated and aerated with a maxi jet 1200 24/7. Currently I am doing two 20gal water changes per week trying to battle the Red Demon. I have stopped all liquid additives since reading your site(you know, things I can't test for) the only additives I use right now are B-Ionic #1/2 if and when needed. Also I have cut down on feeding from once a day to every second day and stopped using garlic, Selcon, Zoe, and Zoecon thinking I was polluting the water. For feeding right now I am using Spectrum pellets, and seaweed sheets on a clip occasionally. I also stopped using frozen mysis figuring I was polluting the water.
<Everything sounds good here.>
My water parameters are always good.
<Water parameters are not necessarily indicative of good water quality.>
Test kits are all Salifert and a refractometer. I also bought an oxygen test kit and after reading up on these kits I found out it's hard to get an accurate reading. With the oxygen test I get a reading of 4ppm which I know is very low so I tested my ro/di water before and after aerating and I only got a reading of 5ppm. My newly mixed salt water after aerating for 7 days I only get a reading of 4ppm same as the tank. My latest attempt was getting a silicate test kit which reads no silicates, and I have started dosing with Kalk to see if that helps, plus I'm keeping the lights off during the day and only using them when I get home for about 5 hrs.
Readings are as follows for water parameters.
temp 78/79
ph 8.2
ammonia 0
nitrite 0
nitrate 0 also 0 in my ro/di water
phosphate 0 also 0 in my ro/di water
calcium 400/420
dkH 9.6/10
mg 1250/1300
sg 1.026
So now for my livestock.
1 true Percula 2 1/2" (Amphiprion Percula)
1 Royal Gramma 2 1/2" (Gramma Loreto)
1 Flame Angel 2" (Centropyge Loricula)
1 Pajama Cardinal 2" (Sphaeramia Nematoptera)
1 Yellow Watchman Goby 2 1/2" (Cryptocentrus cinctus)
1 Blue Hippo Tang 3 1/2" (Paracanthurus Hepatus) I know he's been, as B. Fenner calls it "bonsaied" not intentionally but from lack of knowledge and info. when starting this hobby.
<Yes, tank is really too small for the Hippo. And you are borderline on stocking if not overstocked. One needs to keep in mind that fish grow and what was once thought understocked can now overstocked.>
1 Black Brittlestar (Ophiocoma)
1 small leather
1 brain (Trachyphyllia)
1 flower pot (Goniopora)
1 pink tip Anemone (Condylactis)
<Mmm, not good mixing anemones with corals in this volume of water. Mmm, no crabs or snails for clean up?>
I am new to the scientific names so please go easy on me. As for the Goniopora I am not sure if it is one (pic attached) because I've read that they're not easy to keep and usually die but I've had this one for 3 1/2 yrs and I have never fed it or done anything special for it and to me it seems beautiful.
<Pic way too small but does appear to be a Goniopora. Count the tentacles on a polyp, should be 24. This coral is likely doing well because they prefer somewhat less than perfect water in terms of nutrient levels.>
All the fish, coral and anemone above, except for the Pajama Cardinal, Flame Angel and Goniopora I have had for 6 1/2yrs, the Pajama, Flame and Goniopora for 3 1/2yrs. My fish have never been sick, never scratch on the rocks and never had problems with Ich. The day I put the baby Clown into the tank she went right into the Anemone and has been living there for 6 1/2 yrs and will bite me if I put my hand near it. I haven't lost a fish in 6 1/2 years.
<Great!>
So basically that is my whole setup, please tell me that I'm not overstocked I would hate to have to move someone out.
<You are close and will be overstocked as these fishes grow.>
If I am I guess I will have to go to a bigger tank. Sorry for this long letter about the same old problem that you hear everyday but I'm at wits end, I love this hobby and I enjoy my aquarium but this problem is so discouraging it's making me want to give it up. Again thanks to all the people of WWM for their dedication to this hobby.
<Brian, other than what you have read about Cyano control on WWM, there is not much I can add other than what I mentioned above. The main goal is to control/lower dissolved nutrients, and with the use of a sump and skimmer, you really should not have any oxygen deficiency in your system. I have been reading good reports from folks using bio pellets with a reactor.
This is actually a dry form of vodka dosing, and although this system does a great job of lowering nitrates/phosphates, it also starves the Cyano in the process. Folks using this method of nutrient control will initially see an increased growth in Cyano, but then the growth drops significantly to a point where the Cyano is completely eradicated. This development period can last anywhere between three to four weeks. I have been seriously considering using this method of control in the very near future.
James (Salty Dog)>
Brian

Re The Red Demon "Cyano" HELP/Cyano Control 5/5/2011- 9/28/11
Hi there James(Salty Dog),
<Hello Brian>
Well it's been a couple of months since I wrote my letter about my Cyano problem and I have been patient and not expecting results overnight. I followed your advice and changed the following. The Hippo Tang was moved out, I removed the filter floss from the first compartment of my sump and placed it after the skimmer and now I change it out weekly (which I wasn't doing before). I still have my Polyfilter and Purigen after the skimmer.
<Good.>
I do find that the Tunze pulls out more than the Vertex 100 did. My husbandry is still the same except I don't do two 20g water changes a week, now I only do one 10/15g per week (it was getting expensive using Tropic Marin Pro Reef salt as I live in Canada and it's $100.00 per bucket).
<Yikes.>
I also purchased a reactor with the Biopellets and have been running that for about 3 months now. I have added a cleanup crew of about 18 Cerith snails, 15 Astrea snails and a Cleaner Shrimp. My water parameters are always stable and same numbers that I sent you in my last message. I find that the Cyano has cleared up quite a bit but I still have it coming back I haven't gotten rid of it completely. I removed the live rock that was at the top (about 8 or 9 pieces) that was really covered with the red slime and placed them into a 15g tub with a power head, a canister filter with a Polyfilter and the Vertex100 skimmer for about 3 months to clean the rock.
Now that the rock is clean of Cyano I returned it back to my tank and within a month that cleaned rock is now developing some kind of brown hair algae. My other question I have, well actually two, would you have any idea why my Biopellets have turned red? I'm thinking it has to do with the Cyano. My filter floss turns red also.
<If you were brushing the Cyano off the rock this would happen. And if so, it is the worst thing you can do, you are just spreading the &%*&^%$ stuff to other areas of the tank.>
Is it possible that the Biopellets have removed the Cyano and now leaching it back into the sump where my filter floss and Polyfilter absorbs it and turns red?
<Possibly. You may want to try Boyd's Chemiclean which is likely the best and most effective product in removing Cyano, but you do have to follow the instructions to the tee. I'm not a fan of using these type products but I have heard good reviews on the product, and sometimes you are faced with no other alternative. I know a few experienced aquarist who resort to this product before Cyano gets out of control. Have you increased your flow rate since the last email? You might want to check the skimmer's venturi pathways to ensure no calcium or debris build is present which will greatly reduce the efficiency of the skimmer. The lines/fittings are pretty small so it doesn't take much of a build up to reduce air flow to the venturi.>
My other question is, have you ever heard of a Percula divorcing it's Anemone? My Percula that I've had for 7 years now has been living in it's Anemone since the day I put him in the tank and just lately he doesn't go near it anymore he now sleeps on the other side of the tank in the corner upright bobbing the way they do. Even during the day he won't go near it and if the Flame Angel harasses him a bit he still won't retreat to it the way he used to.
<Mmm, may be the fish is aging and having a problem producing the protective slime which protects the fish from being stung by the anemone.
Bob may input here as well.>
Well I have to say thanks in advance and again praise all the men and women of WWB for everything you do.
Thanks
<You're welcome. James (Salty Dog)>
Brian

Cyanobacteria, rdg. 4/12/11
Hi crew, first I want to thank you for the great job you guys do on the web page. Guys im having problems with Cyano I don't know how to control it.
<... this is gone over and over; elucidated on WWM: http://wetwebmedia.com/bluegralgae.htm
and the linked files above. Simply read>
I have gone to my lfs but it seems like all they do is sell me something different.
<Quelle surprise. Not>
I use r.o water that I buy from them and I get my water tested all the time. They told me all my water perimeters are fine, I don't have them on hand now but they all read normal. Is a 55g with about 60 lb live rock and about 2" live sand 20 blue hermit crabs two turbo snail and ten more reg snails.
<... won't eat this>
I have a pair of mated clowns and a Hawkeye. Wet dry filter
<Part of the cause>
from pro clear a Coralife super skimmer(any good)
<... see WWM... Learn to/use the search tool, indices>
I get almost nothing in collection cup all week. And one Koralia. My question is how do I stop it from coming back? I've done water changes, and added all sorts of things bought from my lfs. I've read all trough the wwm but all cases seem different. Please help me im running out of ideas and money!! Thank you and I hope to hear from you guys soon.
<Keep reading. Bob Fenner>

Re: BGA 2/13/11
Howzit, Bob?
<Fine>
Sorry for the delay in follow up. Here is a picture of the algae I'm dealing with. I generally keep 3-4 hermit crabs, and 4-5 snails of different varieties,
<... won't eat this>
though I've had problems with the snails lasting any amount of time. A Lawnmower Blenny actually starved to death in this system,
<Unpalatable to Salarias, Atrosalarias spp>
and a Coral Beauty did well feeding on the turf algae for about a year, but then perished around the same time the algae got really bad. I'm guessing it was a water quality issue, because the angel's fins had started to get ragged before it died. I would like to try adding a C. Argi to the current stock, though.
I was intrigued by your suggestion that there could be an issue with the rock or the sand bed leaching nutrients somehow. Given how much trial-and-error it would take to isolate that particular source, do you see any benefit in trying a UV sterilizer? I've tried to subscribe to the "more biology and less technology" approach, but I can't see how to get ahead of the algae without tearing down this system and starting over. Also, if I isolate my corals in another tank, am I just spreading algae spores into another system and asking for trouble there, too?
Mahalo,
Scott
<Read: http://wetwebmedia.com/bluegralgae.htm
and the linked files above. B>