Algae/fungus/sponge ID plz

[mcarroll]

PHOTO

FACTS
The patch in the photo is about 2.5" wide, growing on the side of a Seio prop pump.

The coloration is an artifact of the photo - in reality it is black or dark grey and fades to white in places.

It does not grow in sheets.

It does not seem to trap gas bubbles - instead it grows in a "meaty" form. Sort of fibrous.

It does not favor "dead zones".

It does seem to require light - while it has migrated to the second display, it has never (AFAIK) migrated to my sump.

STORY
It's been in the tank since the very first rock went in ~7 years ago when I suspected that it could be a sponge or something interesting. It has survived all (2? 3?) of the Chemiclean treatments this tank has been through in its life and showed no sign of being affected by any of the treatments whatsoever. (The last treatment was several years ago.)

Thankfully it doesn't seem to grow fast and it is reasonably easy to remove thanks to its chunky nature - but it seems unstoppable and always (slowly, like The Mummy) returns.

Given its track record in my tank and its growth form, I'm guessing at this stage that this is not a type of cyanobacteria...but can anyone deny that and/or confirm what it might actually be?

Thanks in advance!

P.S. I was going to post this in General Discussion....let me know if this is off-topic for this forum.

 

[brandon429]

eventually it w likely come down to gfo use and measured phos control above whatever standard is currently in place.

need a standing back fts

to look for sb accumulations, signs of aging and not cleaning, coralline spotting in the corners of the tank to gauge aging and waste usage in the tank, algae loading of other kinds and lastlly areas of coral plating vs no plating compared to age of tank. all that from a stand away full tank shot

 

[mcarroll]

Forgot to add this stuff does not ebb and flow with nutrients. (I have green and red algae that do.)

Was actually hoping for a positive ID vs a fix.

 

[brandon429]

I couldnt tell well enough from that one pic though, was thinking other spots in different lighting from the fts would show. going off that alone, id have to call cyanobacteria. i know you listed thats not suspect but thats what the velvety covering looks like in the pic

what about p04 levels for the tank, in good standing?

 

[mcarroll]

This stuff more or less gave way to the golden algae/diatoms/haptophytes/chrysophytes/whatever that got its own thread.

If this stuff comes back, I'll be doing the H2O2 test on it for sure.

(Not sure how I so completely lost this thread!)