whaaaaaaaaaat is this ???

[dclegern]

Still grasping at straws ya'll over this white thorny mass growing from under my live rocks.
some say it's a parasite, some a fungus, others say a sponge, etc.
it was cool at first (rapid growth in a slow tank) but once it started choking out some of the wanted. I found as much as I could, and scrubbed it off in a holding tank.

I wish I had a good picture, but look around the edges of the sponge.
almost like a thorny spider web, very white. started near the skimmer.

Aaaaaaaaaaaaaaaaargh!!