ID needed!

[10k]

Can anyone tell me what these are. I have an idea, but want to make sure. Thanx in advance!
<a href="http://www.reefjunkie.net/uros.html" target="_blank">www.reefjunkie.net/uros.html</a>

 

[bob the builder]

Looks like somthing in your tank mated and laid some sort of egg sack . Thats all i could think of.

 

[byrself]

i don't know, but i had something similar on a piece of lr i put in my "urchin" tank. looked like little round balls with a hole down the middle. the urchin made a meal of them whatever they were

 

[saltylake]

it is a type of sponge. I have similar ones that are yellow in my tank.

 

[10k]

I thought it looked like a sponge, just wanted to make sure I wasn't seeing things. Better safe than sorry... Thanks for the help everyone!

 

[jakob4001]

looks like a sponge to me; we have those occasionally too; could be cause d by some type of snail or worm though

 

[karlas]

looks like an encrusting sponge i have one also. the small yellow ones are ball sponges