Sponge or Worm?

[Kieko250]

Hello everyone , I just noticed these under my live rocks. Some are skinny one is fat. Help with ID please.

 

[i cant think]

They look somewhat like sponges, are they only in the dark?

 

[Kieko250]

Yes under rocks

 

[i cant think]

Yes under rocks

Yeah, to me, that’s sponges - Usually worms don’t stay under rocks

 

[WheatToast]

That is a Pineapple sponge. Mine never bothered anyone.

 

[i cant think]

That is a Pineapple sponge. Mine never bothered anyone.

I agree with this, it looks a lot like a pineapple. I’ve not had any yet but I’ve had similar ones and they just grow casually, ignoring everyone else

 

[Kieko250]

Thanks. Was afraid it was some type of worm

 

[James_O]

Looks like pineapple sponges to me. Natural filters and harmless.