Green Algae Bloom advice please!

[cek1313]

Well as long as I have kept clowns (among other fish) occasionaly I have bouts with algae that defy everything I try to keep in check. Recently only one (thank goodness) 20L that has a pair of pink skunks has over the last week become increasingly green in appearance to the point where I can't even see the clowns until they appear at the surface anxious to eat. Obviously I have a dominant green algae bloom but am unsure what exactly to do. Here is what I have done so far:

Changed 50% of the water--which helped visibility, but returned to zero visibillity within ~3 days. All tests are fine (NH4 0.0, NO2 0.0 NO3 ~5ppm, PH 8.2 morning and 8.0 evening, calcium ~400ppm.

So I cut back feedings to every other day thinking this was a high nutrient issue--no luck.

My ideas: introduce a macroalage to out-compete, tear down the tank, turn off the lights for a couple days (I already reduced the light cycle to 8 hrs/day (tank as (2) 65W PC one 10000K and one Actinic 03).

The fish are doing just fine--if they would lay eggs, the fry would probably love all this "plankton".

Ideas?????

 

[Russ Braaten]

To get rid of this bloom I would reduce the 10K light to about 4 hours a day. The actinic light shouldn't make it grow much. I would also look at where daylight or other lamps are lighting up the tank. If you have a bright room or window lighting up the tank you should cover the tank with dark paper for a while. I have a 100 watt lamp near my tank and I find when I use that lamp more often I get a green algae growth in a circle around the area of the lamp light

 

[captbunzo]

Whatever you do, don't tear the tank down.

I'd agree with the keeping the lights on for shorter for a while. What sort of corals are in the tank?

 

[Travis L. Stevens]

If there are no corals in the tank, I would just keep the lights off. Run a little carbon to help suck some unknown things out, and keep doing waterchanges. I've had my battles with green water and any detectable nitrates will keep the green coming back.

 

[lightbolt75]

Use a UV sterilizer. Works wonders.....

 

[Travis L. Stevens]

<a href=showthread.php?s=&postid=7672401#post7672401 target=_blank>Originally posted</a> by lightbolt75
Use a UV sterilizer. Works wonders.....

This is only a short term solution though. Yes, UV will kill the phytoplankton, but as it dies it has to be removed either through heavy skimming and/or waterchanges. If it is not removed in a timely fashion, it will go through the cycle again only to later bloom again. A UV Sterilizer cannot kill everything. Also, if you do not control your nutrients, then there are many other things that can later go wrong. Do I advocate a sterile, nutrient free tank? No, not necessarily. But it does help make things easier as your tank goes through it's many stages. I believe that nutrients has it's place in every tank, and you must properly control it to suit your tank's needs. For example, a tank with things like Goniopora, Tridacna clams, Euphyllia, Sarcophyton, and other various soft corals, a small amount of nutrients is prefered over a nutrient free environment. After all, these specimens do enjoy a little nutrients mainly used to grow, but also found in their natural evironments.

 

[cek1313]

I greatly appreciate the advice offered. I have turned the lights completely off since I began this thread and ever so slowly, I am beginning to be able to see about 2-4 inches into the tank. There are no corals, only a pair of skunks and a "fake" (rubber bands tied to together) anemone that they host in. There is about 25 lbs LR but nothing significant growing on it. This setup is approx 13-14 months old.

I am going to do 50% WCs until its gone, keep the food levels down (which is difficult b/c I woud like to spawn these two) and see if I can't knock it out. I have never run a UV sterlizer on any of my clown tanks but have used it on other reef setups with great success. Of course I also have multiple tanks that do not have this problem and no UV is present. Obviously something fell out of sync and allowed the green bloom to take over. Any other ideas are welcome

 

[Travis L. Stevens]

I don't know if I would do 50% changes. With the lights out, the phytoplankton will gradually die. That large of waterchanges could also stress out your fish. You want them in tip top shape after all. Might I suggest 10-20% waterchanges every week to two weeks.

 

[cek1313]

I'll cut down per your advice. My main concern isn't so much ridding the tank of the bloom but keeping it from returning once I resume a (limited) lighting schedule and semi-regular feedings. The fish receive ample ambient light from other tanks in the room, but no direct light.

Tearing down the tank is always a last resort for me and considering the health of the fish to be optimal, I'd hate to do that. An ideas for preventing the bloom once it is gone?

 

[captbunzo]

I would say the more important question is to identify why the bloom occurred in the first place. Maybe I missed it above, but has that been sufficiently decided upon?

 

[cek1313]

Paul--exactly!! I just don't know why. I truly keep all of my tanks within very specific paramters but obviously there are minute things I can not account for. IMO there is an imbalance of some type but all tests are within acceptable range and very comparable to the tests on my other tanks. My experience tells me to just keep the lights off, change the water and when all is clear, resume with a limited light cycle (maybe 2-4 hrs to start and work back up to 8-10 for actinic and 6-8 for 10000K) I will likely add some caulerpa has I have tons and tons of it growing like a weed and if it is a NO3/PO4 issue the caulerpa should easily out-compete and then all I have to do is harvest regularly.

 

[captbunzo]

Of course, I am biased as I wouldn't just about ever use Caulerpa in a tank. But I wouldn't add Caulerpa to such a small tank. It is a very chemically noxious macroalgae and will significantly increase the amount of immeasurable stuff in the tank.

Of course, like I said, I am biased.

Couple questions - do you regularly run carbon in the tank? What sort of filtration are you using? Can you add any phosban to the system?

Those would be some of my ideas.

 

[cek1313]

On this tank, water movement is done by a whisper 300 (no media/sponges inside) and two small water pumps along with about 20-30lbs LR. I have run carbon in the last weeks coupled with weekly 25%-50% WC which cleared it up significantly (temporarily). Typically I don't run carbon in this particular tank otherwise. I have hang-ons that I may try running phosban in although tests for phosphates are low (< .1ppm). Recently the NO3 has begun to drop which I would normally think is due to the anaerobic bacteria in the LR but since it has been setup over a year now, I am thinking that it is the plankton bloom using it up. This means that it will bottom out soon and possible kill itself.

Thanks again to everyone for the responses and keep them coming--surely I'm not the only one who has experience green water

 

[djc1026]

How old are the PC bulbs? Deteriorating spectrums have been known to contribute to algae blooms.

Just another thought.

Dave

 

[cek1313]

djc--definitely true however these are about 6-8 months. I usually replace my PCs about 1X per YR and halides every 18 months. Since the only visible multicellular thing in the tank are the clowns, I was thinking of placing a 14000K halide over the tank. That may be too much for them and then again it may be like pouring NaNO3 into the tank

 

[Prater]

Just went through the bloom on my 75 gallon fish only. I just left everything alone and it took three weeks to completely clear up. Could not see but just a few inches into the tank. Did not seem to affect the fish at all.

 

[Brandino007]

I had this happen to me a few months back and I tried everything but nothing touched the stuff until I just turned the lights off for a week then everything was crystal clear! And it never came back. Too bad hair isnt that easy to get rid of lol

 

[scott0615]

I have always followed the following theory - algae is living - anything living will not live without a food source. This tank has a nutrient the algae is thriving off of [not necessarily phosphate or nitrate]. Look closely at your foods and nutrient supplements - anything organic will feed different types of algae. Increase the export of nutrients [polyfilters, purigen, carbon, phosphate remover, etc.] and limit the import of nutrients. A uv sterilizer will kill any type of free floating algae and I would not have a tank without one [lots of thoughts and theories about that!].

 

[cek1313]

The lights have now been off for almost one week with maybe a ~20% improvement in visibility. I do agree scott0615 that this stemmed from a nutrient issue that allowed the bloom to take over. I am going to move one of my UVs over to this tank and see how we do. As far as food, these guys were getting frozen brine ever day coupled with occasional live brine, chopped shrimp and once a week I would soak the live brine in selcon which I think may the culprit (or at least one of them due to its high enrichment). I'll stop the selcon and only use live and frozen brine for awhile and start the UV this evening. Thanks again to everyone for their ideas!

 

[herpchat]

Why the hatered of Caulerpa?

I think its wonderful stuff.