Whitish-yellow film/slime on rocks?

[Goubli]

So I’m running a lower nutrient sps setup that’s been running for 10 months. I have a minimal cleanup crew and a solo flame hawkfish.

pH is 8 and consistently 7.9 or higher
Nitrates <1
Phos <0.08
Alk 8 ish
Ca 440
Dosing two part Bionic on apex
Running gfo

Basically tank looks solid w all sps growing.

I had to go out of state for extended period and wife took care of tank (fed fish). I saw her def overfeed when I returned so not sure if that could be a cause of my issue. I have been back a month w two water changes and stable parameters.

This filmy stuff popped up while I was gone and I haven’t seen much change despite ratcheting down feeds and changing lighting duration. Sand gets caught in it, and the top layer can be seen flowing with current. It’s pretty adherent to the rock, and I can’t tell if it is infringing on sps spread yet but it’s only now close enough to colonies to tell if it will start to affect them.

There are no air bubbles like cyano, and my biologist friend suspects it’s bacterial.

I’m on the fence about getting an urchin or two to see if they would scrape it off the rocks. I don’t really know what to do about it, but I’ve had my fill.

Any ideas what it is or how to deal w it?

Any advice appreciated!
Thanks,

Steve

 

[NowGlazeIT]

Do you use an ATO? I had an issue with my ATO not having a tight lid and a lot of nasty white stuff bloomed in my ATO and then this bacteria algea started growing all over and attacking my zoas and gsp

 

[John3]

I saw something very similar in my tank and it came and went on it’s own fairly quickly. Never had much of a chance to look into it. How long has it been there?

 

[Goubli]

My auto top off has a lid and is contained in a compartment behind the tank (Red Sea tank).

I'd say it's been around for a couple months maybe. No livestock or coral has been added since mid-September. My coralline algae is finally beginning to spread so I'm hoping it may outcompete it. I've been patient hoping it may die back. I am ok w waiting it out, but I also don't want to let it get out of control. It seems to be stable or possibly lessening slightly.

 

[Goubli]

Double post. Sorry

 

[Goubli]

No one has any ideas or has seen this before?

 

[NowGlazeIT]

Do you have any scents running in the house like frangrence fumes? that’s been known to cause bacterial blooms but what has me boggled is I’ve seen this concentrated on zoas or gps and related mat growing colonies but never so thick on the rock work. still we should look for anyone that has seen this exact issue. #reefsquad

 

[saltyfilmfolks]

I’d go with a diatom or chrystophytese.

Run carbon , hit al of it with a tooth brush , dip the sick corals in an RX or revive.

Like the giant dino thread, look at the nutrients and make sure one or the other is not limited (absolute zero)

 

[NowGlazeIT]

Do you have any scents running in the house like frangrence fumes? that’s been known to cause bacterial blooms but what has me boggled is I’ve seen this concentrated on zoas or gps and related mat growing colonies but never so thick on the rock work. still we should look for anyone that has seen this exact issue. #reefsquad

 

[NowGlazeIT]

Dang this reefsquad member @saltyfilmfolks must have sensed I was about to tag them hahah that’s what I’m talking about

 

[KJ]

Look like fungal or bacterial mats.

 

[saltyfilmfolks]

Dang this reefsquad member @saltyfilmfolks must have sensed I was about to tag them hahah that’s what I’m talking about

Lol.

Look like fungal or bacterial mats.

Yup. Myself , I’d feel it with my fingers and smell it.

 

[Goubli]

So tomorrow I will be doing water change and testing. I will pull out a small rock and smell it. No fragrances going in the house, but maybe back in December we had some candles going but they were distant from the tank (30-60') and rooms apart.

It seems like there was some of this already on the rocks prior to the candles.

What should I be smelling that helps clue me into what it may be?

Thanks again

 

[Goubli]

Ok, so I took out a rock w the slime and its fairly slick and doesn't peel or scrape off. Also, it has no smell. In other words, it smells just like normal rock.

I tested my water today and nutrients are super low. Nitrates 0, Phosphate 0.003, Alk 8.5, Ca 410-20, Mg 1400, salinity 36 ppt

So, I am adding 3 new fish today and will start feeding a bit more heavily since I only have a solo flame hawk. Maybe it will start clearing up. Any other ideas? I kind of want to hold off on carbon for right this minute.

 

[KCSUMPS]

Did you ever figure out what this was or did it go away?