What the heck is this? Is it even a coral?

[michaelp]

Found this on the bottom of my tank. It has a small piece of rock attached to it. It's kind of hairy or striated, and completely white. I have no clue what it is or how it go there? I moved it to the light to see if it grows.

 

[jhale]

hard to see in the pics, it might be a sponge.

 

[michaelp]

Ok, I got out the SLR. This is better...

 

[Killerdrgn]

yeah could be a sponge. Or some cotton that got stuck on the rock:lol:

 

[reefman]

it look like the foot of a clam.

 

[MikeyZO]

lol it does look like a piece of fuzzy stuff you see floating in the air every now and again.

 

[Kaz289]

cotton growth

I have similar stuff growing on 1 of my rocks, it is about the size of a nickel and looks like a coton ball. I only have it in 1 place. Anyone know what it is? I took a pic but im working with a cell phone so i did my best its just to the right of the zoa and just below the blue crabs left leg in this pic.