Is this a sponge, fungus or other in my sump?

[chonsworth]

This is the sump of my tank, it' about 8 months old. I put a little bit of rock from previous nano tank in here to bring pods in, etc. I was doing maintenance and noticed this stuff on the rock in the sump (it's behind my skimmer so I don't look back there much).

I -think- it's a sponge? But maybe it's fungus or something else? Is it a friend or foe? (usually I read that sponges are 'fine') - but can't hurt to double check!

 

[xdcbenoitxd]

Sort of looks like tunicates to me (filter feeders) but I could be wrong.

 

[ISpeakForTheSeas]

It seems to be a sponge - harmless filter feeder.

 

[chonsworth]

Seems both ideas are harmless and not a fungus

 

[Miami Reef]

It reminds me of the texture of BJD. I’m curious. Does it blow away if you squirt it with a turkey bastet?

 

[chonsworth]

It reminds me of the texture of BJD. I’m curious. Does it blow away if you squirt it with a turkey bastet?

Finally got down there for some basting - nothing blew away, quite stuck!

 

[Turkey head]

I have what looks to be the same thing in my tank. It’s an encrusting sponge. I haven’t noticed any negative effects from it. It’s not where I can get a decent picture though. It’s on the underside of some rocks