What the HECK is this?!?!?!?!

[sgrosenb]

I found this under one of my rocks in the back of the tank... Nasty. Anyone know what it is, where it came from, or what I should do with it?

 

[Dante_JoseCuerv]

Looks like some sort of non-photosynthetic sponge.

 

[Steve175]

Looks like some sort of non-photosynthetic sponge.

+1. Would have left it. Not great chance of making it after prolonged exposure to air: if small tank (< 75G) would now scrape it off so that it doesn't soil tank. $0.02

 

[JeF4y]

It's - soon to be dead - sponge.

I found a few in my tank as well. Freaked me out at first, much like the first bristleworm I saw when I first started. LOL.

 

[travis32]

I have a huge brownish red one just like that under a rock. I think it looks cool. And it looks much like my yellow sponges in design only about 3 inches in diameter. I like it...

 

[sanchoy]

that is confirmation a sponge. they are not harmful, however if you expose to air it will be dead.. you have to scrape it off now and do not place back into tank once you expose to air because it will die and pollute your tank..

next time leave be.

 

[llewoh05]

Bet it took forever for it to grow that big. Sorry to see it go.