Fungus or Bacteria ID?

[jsteinmeyer]

In a puzzling situation here that I've never seen before. It seems as if I've introduced some sort of fungus or bacteria to my tank. It's white, fuzzy and coated just about every piece of rock in the tank. I'm also battling what i believe is some thick cyano (Brown slime curdling the sand and coating rock too).

I've battled low alkalinity/pH from the get-go but I'm running an ULN system, no fish in last 4 months and mixed reef. But the (Believed) cyano and this fuzzy white stuff has suffocated my zoa garden and other corals, so I have to figure out what I can do to fix this. I've tried chemiclean and a couple 50% water changes over the last month to no avail. I have a feeling I'm fighting an uphill battle since it's not likely a water quality issue.

For starters, can anyone give me some info or an ID on this fuzzy white stuff?

[sean357]

Can't remember the name off the top of my head but I battled this stuff in a previous tank where I used BRS reefsaver rock without properly treating the rock with acid, etc. What kind of rock are you using? Is it possible the rock is leaching phosphate? That at least is what caused this in my old tank.

[mcgyvr]

Can you take another picture with the blue channels turned way down/off?
Proper color rendition is important with identifications and all that blue doesn't show real colors..

May be chrystophytes algae though..

[devimik]

+1 on chrysophytes

[jsteinmeyer]

Here's a better shot with brighter whites. I set the tank up with BRS dry rock and bottle of bacteria. From the little I've read on chrysophytes, it sounds like a silica test could be handy to identify part of the problem. How does phosphates play into growth of chrysophytes? I've been reading 0ppm on Hanna po4 checker.

[jsteinmeyer]

I thought I'd bump this and update things. All specs are still under control. Alk and Ca still a bit lower than I'd want them to be, but I haven't seen how this would correlate to my issue here.

After manual removal from the rocks and some of the "slime" off the sand, I added GFO, started feeding reef chili once per day for about a week. I think this was my main issue and why chrysophytes or even dinos could be my ID. This was an ULN system without fish, so I was target feeding corals MAYBE once per week.

I went on vacation this past weekend and performed a 3-day blackout. Turned on actinics today and while the rocks looks better, a lot of the "white fuzziness" is gone however the thick brown slime is just as bad as its ever been.

My determination now is that I'm either battling dinos or potentially even diatoms. I haven't had much luck in finding some good advice in battling either of these. Does anyone have any links to other forums that may help me out? Should I continue my current patterns of feeding more, less water changes and manual removal? Any suggestions are appreciated!