What is this mass??

[Wicket30]

I was looking through my tank and found this black mass, looks like it has some tubes coming out of it. I don't think it moves, its just tucked in between some rocks. Any ideas? TIA!

 

[EricR]

Black tunicate?

 

[EeyoreIsMySpiritAnimal]

@ISpeakForTheSeas

 

[ISpeakForTheSeas]

Yeah, I’m thinking a black sponge of some kind, though tunicate is a good guess (particularly with what looks like a huge siphon hole in the center of the black mass). If you look at the left side of the mass just above the siphon hole, however, you can see a tansparent, black-tinted tube that would seem to be a strong indicator that it’s a sponge. Either way, it’s a harmless filter feeder, and it’s got some nice coloration.