Is this a Sponge?
 

I'm not sure what this is - and the picture isn't that great as the 'sponge' is growing away from the front of the tank. The tubes at the top sometimes appear to inflate and deflate at different times. I never new just how aptly named "live" rock is. I don't even have fish yet and the tank keeps me occupied for hours :biggrin:

Could be a sponge, hard to say from the picture. Could also be a tunicate.

Hard to tell...picture is a little blurry...sponges can take on a variety of shapes, if you can get a clearer picture it would be nice..
It doesn't look like this though does it....
http://images.google.ca/images?hl=en...-8&sa=N&tab=wi

Sorry I couldn't resist....

I thought it was going to be a link to Seinfeld. I wonder if his tank is sponge-worthy?

That was funny! And no, it doesn't look like that at all :biggrin:

I'll try and get a better picture, but it's in a difficult spot in the tank (at this point everything is behind algae!!)