Could it be cucumber "poo" ?

I don't know...he has this cluster and another growing a few inches away.
He doesn't have a cucumber in the tank.

Sponges. I've had them in my tank, just not in huge clusters like that.

I also suspect they are sponges. I've seen a few of this type but never in such an impressive colony. Very cool! :wink:

I'm not convinced they are sponges by the way they are sitting there.

You have several scientists scratching their heads over on the other site I posted this on for you. One of them suspects sponges as well, but thinks the layout would be very unusual. They want you to siphon some out and slice one in half and photograph the inside. Could you do that?

I can ask him. I was there again for a bit and noticed that he has a few of these colonies growing all over his tank. He thinks they are sponges too but isn't really sure. Thanks Myka and I'll post more pics from different angles...kinda hard cuz they don't grow in the light...mostly under ledges or within the rock. I'll try to stop by there tomorrow and post more pics tomorrow or wednesday.

Heres a picture of the balls split...I did the best I could
http://i944.photobucket.com/albums/a...cXx/photo6.jpg

the texture was rough...no slim or anything like that. When they were squeezed they stayed flat. I am starting to push toward sponges myself but would like to know what kind.

Ya, those are going to be sponges. Darn...they didn't look like it when they were wet! I'll still send the photo to my friends, but I'm sure they will say sponges.

Thanks for all your help.