What is That Coral?

[BigTuna321]

This coral is growing off the live rock i recently bought. It lives in a tube kind of thing and mainly stays out but every once in a while he goes back in his hole. Sorry about the picture it was hard to take due to the slanting glass. Anything else you know about it would be appreciated like size, water specs, etc thanks.


http://reefcentral.com/gallery/showphoto.php?photo=261116

 

[Murphs205]

they look like little feather dusters/ filter feeders ,, i have a bunch of them that pop in and out a lot ,, do they get startled and suck back into their tubes real quick ?

 

[Kreeger1]

Tube worms