Calothrix? Dinos? Something else?

[NigeltheBold]

I've been battling this stuff for months and I don't know what to do. At first I thought it was Dinos, but I did the coffee filter test, and theoretically ruled out dinos. Now I'm suspecting Calothrix, but I don't know. It's long and stringy , and looks like fuzz on the rocks. There's probably some green hair and turf algae in there as well. When I manually remove as much of the stringy stuff as I can with a brush, it comes back in a day or two. It's only on the hard surfaces of the tank and there's nothing on the sand bed at all. I've tried lowering nitrates and phosphates, I've been using Brightwell MicroBacter Clean for several weeks, I've tried dosing peroxide for a couple of weeks, and none of it had any effect, even after scrubbing. Most recently, I tried chemiclean, and that did nothing except make my skimmer go crazy and pump a ton of micro bubbles into the tank (which you can see in the pics). I don't know what else to do. I can't take out all of the rocks and spray them with peroxide because most of my rocks have corals on them. I'm scared to do a blackout because I don't want to lose my corals. I'm stuck.

Parameters:

110 gallon Reefer tank w/ 29 gallon sump
Running a ReefMat, RSK600 skimmer, 36W UV sterilizer, carbon reactor
Salinity: 24ppt
Alk: 9.1
Nitrate: 0.15ppm
Phosphate: .01ppm

I know nitrates are too low, I'm trying to bring them up to 2 or 3ppm but I'm guessing all of the bacteria that I've added are making that difficult.

I've added lots of snails and hermits to my cleanup crew, but they don't seem to have much of an impact. I'm adding roughly 100 more snails and crabs from ReefCleaners tomorrow.

What else can I do?

 

[dwest]

I don’t know what it is. But it appears your corals are doing well so that’s a really good thing. I would siphon it out and not add any more chemical fixes. Eventually coralline algae will dominate and corals will shade the algae. I’m assuming your salinity is a typo?

 

[NigeltheBold]

I don’t know what it is. But it appears your corals are doing well so that’s a really good thing. I would siphon it out and not add any more chemical fixes. Eventually coralline algae will dominate and corals will shade the algae. I’m assuming your salinity is a typo?

Ha! Yes, it's 34ppt, not 24.

It's hard to keep up with siphoning/scrubbing. The stuff grows back pretty quickly. I don't know if I can do it every day until Coraline takes over... that could be awhile.

 

[Reefn'Sven]

Any luck defeating your nuisance algae? Looks mostly like hair algae to me. Maybe a sea hare?

 

[NigeltheBold]

Any luck defeating your nuisance algae? Looks mostly like hair algae to me. Maybe a sea hare?

I finally broke down and used DinoX. I tried a Sea Hare, and it wasn't interested in the stuff.

The DinoX started working overnight. It took awhile to kill everything, and I had to scrub the rocks every now and then to help it along. But it worked. Unfortunately I think I lost a coral and a harlequin shrimp due to the treatment, but I'm not sure.