white oval shaped things growing on rocks

[AquaAdam]

I took some rocks out of my sump today to put into my tank and I noticed that one of the rocks has these white, almost cotton like, oval shaped things growing on it. It looks like the top has shoots that almost resemble that of a flower but I've never seen it before and they weren't visible when I put the rock in the sump a while back. Any ideas?

This is my first attempt uploading a picture to this site so if it doesn't work let me know.

Thanks!

 

[AquaAdam]

Here is another pic.

 

[Dogshowgrl]

Pineapple sponge. harmless

 

[AquaAdam]

OK cool. Never heard of them. Thanks for the reply

 

[mcgyvr]

OK cool. Never heard of them. Thanks for the reply

Bookmark this link for later..
It covers many of the common "oh whats that?" in your tank.
http://www.lionfishlair.com/hitchhiker.shtml