Love getting free stuff

[StartrTank]

So I got my first shipment of livestock in yesterday. Got some more snails and two skunk cleaner shrimp (those guys are fun to watch, they go everywhere together) to finish up my clean up crew. I also got a few starter corals. I got some eagle eye zoos and some radioactive dragon eye zoas, the dragon eyes i ordered 5 and got 11! I also got some purple mushrooms and some red mushrooms. I hadn't noticed last night when I put them in but I think I may have got a free sponge with my red coral. Is this a sponge?

[StartrTank]

It was completely deflated last night, that's how I missed him. But this morning with the lights on it was all puffed up and the "tubes" open and close

[StartrTank]

Can anyone confirm if this is a sponge? The base portion is about 2-2 1/2" fleshy and soft, the "tubes" are maybe 1" when fully extended. The tubes randomly close and then open.

[StartrTank]

97 views and nobody can help me identify what's growing on my mushroom rock?

[Mcgeezer]

Tube worm likely

[Mike Ordner]

Can't help ID but sponges do not deflate, so no it is not a sponge. Might be a palythoa.

[StartrTank]

Does anyone else have an idea? I looked at pictures tube worms and it doesn't look like this to me...

[StartrTank]

Here's another shot of the tubes

[Reef noob_]

featherduster tube it looks like but my guess is a large cocoa worm.

[jeperry3]

Tunicate maybe?