Weird white/grey fuzz

[MrJoel]

Hello folks, I have been trying to figure out what this is for a while with no real luck.
It showed up a few months back and seem to be spreading. I had more on the rocks a month ago before I started replacing some of the rock. I am concerned because it seems to be spreading and the corals are no longer spreading where the growth is. Snails also seem to not be interested.
My parameters seem to be good.
Ammonia: 0
Nitrite: 0
Nitrate: <1 (color barely registers on Red Sea Nitrate test)
PH: 8.2
ALK: 9.4dkh
Cal: 433ppm
Mag: 1280ppm
Phosphate: 0.0122644 ppm (mg/L)
Salinity: 1.0245 sg
Temp: 76-77 range depending on ambient temp (not 96-97 as previously listed)

Here are some images that show the growth I am trying to identify and eliminate if needed. It is even growing on my poor conch. =P
I would prefer to not have to pull corals off rocks they are finally starting to grow onto if possible.

I have seen some posts on similar things from the last decade saying it may be algae or bacteria, but never any real confirmation in the posts on any other forums.
It does not seem to wipe off really as people said bacterial growth would. It took hold when my tank had no fish and only got occasional pellets for the hermits and coral foods where target fed via pipette.
Maybe I am worrying about nothing.

Any guidance would be greatly appreciated.

 

[rygh]

Looks like some sort of bacterial mat to me.
Not normal Cyano though.
I have seen a dark grey like mat once in my tank, when I was overdoing the vinegar dosing.
Not really the same, but slightly similar.
So just guessing.

Are you carbon dosing? Bio-Balls?

Very low Nitrates + Moderate phosphates can benefit bacteria. (look up redfield ratio)
And your parameters seem to say that.

 

[MrJoel]

I was using Red Sea NO3|PO4-X until Mid March when I pulled the skimmer and went with the InTank baskets with chaeto in chamber 2.
looking up the ratio now.
One other detail, I believe it is at least semi photosynthetic as it grows on the top side of the rocks or surfaces with exposure during the photoperiod exclusively. If I turn the rock over the other side is totally clear. This was the case when my rockwork had arches and little caves.

 

[Bruce Spiegelman]

Since it's photosynthetic we know it's not likely to be a sponge. It appears to be a bacterial issue as noted by Rygh. I'd handle it the same way that most handle mats of cyano or fungus. First, see if yo can remove it by siphoning it out. If not use a toothbrush or similar and clean as much as possible while sucking it out as you go. Then do a large water change and do a three day blackout.

 

[Ibn]

I agree with Mark. This reminds me of the bacterial film that I had when I was heavily dosing vodka.

Just another question. Is that ambient temp off by ~10 degrees? Seems awfully high for the corals to look the way that they do.

 

[Bruce Spiegelman]

Btw the reason I switched to vinegar from vodka or NoPox was it doesn't have the Cyano side effect.

 

[MrJoel]

I agree with Mark. This reminds me of the bacterial film that I had when I was heavily dosing vodka.

Just another question. Is that ambient temp off by ~10 degrees? Seems awfully high for the corals to look the way that they do.

That was an error which I fixed now. Should have been 76-77

 

[rygh]

Assuming it is bacterial :
My guess is the Red Sea NO3|PO4-X started it.
The problem : Like Cyano, once started, hard to get rid of.

Suggest the same remedy as Cyano:
Vacuum it off. Repeatedly. If possible, use a small hard plastic tube stuck in your siphon hose, and scrape a bit.
Try GFO for a while.
Try Dr Tim waste away. I am skeptical it will help much, but is safe to try.
If it sticks around though, Chemiclean might be needed.

 

[daddio]

I have bacteria growing in my reef and it looks very different than your pics. Yours looks more like a fungus

 

[daddio]

If it was my reef, I would hook the skimmer back up and crank up the vinegar dosing til I had bacterial snot in the tank . The bacteria from the vinegar dosing would hopefully starve out whatever is growing in your reef.
Cheers! Mark

 

[MrJoel]

About a week ago I started dosing SeaChem flourish Nitrogen. In the week since the fuzz is going away. I will be doing more testing tonight to see if the Phosphate is dropping with the Nitrates being brought up to 2-3ppm from being almost undetectable.
Further testing and recording should show me if this issue was due to an imbalance in the ratio of nitrate to phosphate.