What is this stuff?

[aquella]

About 2 weeks ago I noticed a fluffy, slimy off-white something-or-other "growing" amongst the java moss on the lower sides and underneath of a piece of wood in my tank. I scraped it and the surrounding moss off of the wood and took it in water to my LFS for inspection. My LFS guy didn't seem to know what it was but suggested that maybe it was food that got stuck and molded. I found that unlikely as I have several cory cats, kuhli loaches, and such who keep things tidy.
So, I cleaned off the log as best I could, and hoped it would go away. Now, not 2 weeks later, there's at least as much if not more of this stuff. It seems to grow quite quickly. The rest of the tank is clean, and the wood/java moss has been in the tank for over a year. Has anyone any idea of what it might be?

[AngelMom]

Is it possible that something got trapped between the moss and wood and its a fungal growth? Does it look like "cotton" or more like slime (I'm thinking - ew - dog saliva)?

[aquak]

......oops, no response here!

[AngelMom]

I've looked through every aquarium reference I have and can't find anything like this even listed. The only thing I can think of is that something got trapped in there and a fungus grew on it, but I'm not sure that explains the regrowth after cleaning the wood. Weird.

[aquella]

I don't think it's something that got trapped. It is growing off the side of the wood and also on a plant leaf that's near the wood. It looks more like cotton than slime.

[AngelMom]

If it looks like cotton, then it is most likely fungal in nature. There must be something in that spot that is causing it to grow......usually it is decaying matter, but it could just be slightly rotted wood or a portion of the plant leaf (or stem) that is diseased for some reason.

The fungus is always present in the water, but only takes this form when it attacks "dead" material.

[aquella]

Thank you AngelMom!
It looks quite nasty! Do you know if it is likely to be dangerous to my fishies, or is it just an eyesore?
I wonder if I should throw out the wood, or just give it another good scrubbing and hope for the best.
Do you have any other suggestions of what can be done about it?

[AngelMom]

It should not bother healthy fish. Since it seems to be confined to the wood and the adjacent plant, you could try and treat them out of the tank. Maybe you could save some water in a container on your next water change, set them in it and add some anti-fungal medication? That way you could keep the meds out of the tank and get rid of the gunk, but still keep them

[aquella]

Thank you very much! I'll give it a try.