Algae help!

bpauley · May 16, 2015

Alright, I've been battling this algae for about half a year now and I'm needing some help identifying it so that I can get rid of it! It is a brown algae that grows in a mat in the high light areas of my sandbed. Strong/weak flow does not affect its growth. Water changes and vacuuming the sand does not kill it. The only thing that I have found that affects it is a 3 day lights out period, but it always seems to come back after doing the lights out period. Tank is a 220 gallon with a 100 gallon sump, but this algae was present in my old setup that was a 110. Algae only grows in my display tank under LED lighting, spectrum of lighting doesn't affect it, even going so far as to cut out everything but royal blues and whites. This algae will not grow in the refugium in my sump, even under 100 watts of royal blue/warm white LED's. I have tried hydrogen peroxide dosing while doing a 3 days lights out, did not kill the algae.

Parameters are:
Salinity 1.025
Nitrate 0, or very near 0 with API
pH 8.3 with Apex and API
Alk 9 with API
Magnesium 1140 with API, has been over 1300 with this algae present, level doesn't seem to affect it.
Phosphate 0.086 with Hanna ultra low
Calcium is always over 400

Picture is a macro shot of the algae structure. Anyone have any ideas?

bpauley · May 16, 2015

I should note that even though it seems to grow like cyano, I have dealt with red cyano before and all my attempts at treating this algae the same way have proven ineffective. Last time all it took was multiple water changes with vacuuming the sand to kill the cyano. I have tried that, plus chemical treatments with no success.

Tahoe61 · May 16, 2015

Phosban or GFO type product. Are the members of your cuc sufficient? Anything that turns over the sand?

bpauley · May 16, 2015

Yes have GFO in a TLF 550 reactor, doesn't affect the algae when I change it out. Cleanup crew could be a little better, have a large silver conch and a ton of nassarius and various other snails, but they don't turn over the sand near enough. Would a sand sifting goby or a sand sifting star be better for turning over the sand?

moulton712 · May 16, 2015

Looks like hair algae. My yellow and purple tangs love that stuff. I have to swap out rocks and racks from the frag tank to the display and within hours they have eaten it all. I must have what you have. It's very stubborn. I've tried lights out, peroxide, chemipure elite, gfo/carbon. Nothing works better than a tang.

bpauley · May 16, 2015

Have a purple tang and it doesn't touch the stuff. It also only grows on the sand, have never seen it on the rocks. I did recently get a starry blenny and have seen him eating it a little bit though, so hopefully he helps with the problem.