I've got a 28-gallon JBJ Nano Cube, which has been running for about 16 months. Back in March and April, I had some out-of-town interviews, and got very sloppy with water changes--I think I went three or four weeks without doing one. Mea culpa.
Toward the end of that, I started noticing reddish algae growing on the sand and rocks. I assumed it was cyanobacteria (I'd had an outbreak a few months prior), so I increased skimming and did some extra water changes to make up for it--I figured dissolved organics were the cause, and wasn't too worried. That didn't work, and the algae started spreading FAST. I got some snails to add to my cleanup crew, but when I put them in the tank, they wouldn't open up until I moved them to a place where there was no algae... They actually ended up dying, even though I drip-acclimated them for about four hours. I got a second shipment of snails today, and the same thing is happening. Geez, could the algae be toxic for them?
I'm now thinking that this is a dinoflagellate outbreak rather than cyanobacteria, and I'm pretty worried about the tank right now. All of my corals are closing up and looking very unhappy, and, while my fish seem fine so far, I actually haven't seen my wrasse today... (Maybe I'm getting paranoid?)
Anyway, any advice you'd have would be hugely appreciated. Let me know if I left any information out. I'm attaching some pictures of the outbreak. You can see it's pretty awful at this point.
28-gallon JBJ Nano Cube
150 watts of LEDsó10,000 K
white and royal blue, plus some deep red and ultraviolet that I added a few months ago
Two 425 GPH
powerheads (not too happy with these; getting more like 200 GPH
Two 280 GPH
5-gallon water change every week
Feed mysis shrimp, hard pellets, Phyto-Feast, other treats
Phosphate: near 0
Temperature: 79 degrees F
1 melanurus wrasse
1 3-inch maxima clam (aquacultured, baby!)
1 red fire shrimp
Turban, turbo, nassarius, and nerite snails
Acropora, montipora, birdsnest, zoanthids, blastomussa, ricordea, lithophyllum, leptoseris, pulsing Xenia, galaxea, etc.