Newbie red shrek identification please.

[TAF]

I need help identifying this thing in the middle of the picture.

It is redish and has openings on the upper left and right that close if it gets scared. I first thought it might be some kinda sponge, but I can find no similar pictures.

When it closes the openings it looks like Shrek from the movies... only red instead of green.

http://www.cecolts.com/saltwatertankalbum/full/SNV37790.jpg

[marduc]

hard to tell, but sounds like a tunicate or sea squirt.

[TAF]

Upon reading about sea squirts, it definately appears to be what I have. I take it, it is a good thing to have in the tank?

Are they common in the hobby?

[marduc]

That looks like aquacultured florida LR if so, then they are common hitchhikers on it, years ago when i first set up I had a few on my rock, they eventually died off though. They are beneficial, they will siphon a lot of water through their bodies to extract nutrients from the water, unfortunately I think that in an aquarium environment they may slowly starve.

[TAF]

I've got a whole slew of sponges and clams and several of the sea squirts... so I am feeding phytoplankton each day. I hope this will keep them all going. They seem very happy so far.

Thank You.