vibrant yellow coral?

[Belladauna]

Dunno what this is, but it's not moved so I'm guessing a sps, but I'm not entirely sure. This the the first time I've seen raised little spikes; normally when I check it out it looks very...geometric. I know odd description but I'll but up a picture of that when the little spikes go down.

Any ideas what it is?

 

[Belladauna]

Here's the pics of them with the "spikes" down. It looks slightly translucent at the side.

 

[kay-bee19]

I'm leaning towards it being an encrusting sponge of some sort.

 

[mr_X]

Yep. Looks like sponge to me too.

 

[Belladauna]

How big would it get? Would the hydnophora exesa I have above it be aggressive towards it? And thank you.

 

[mr_X]

I have seen sponge like that 4" in diameter in closed systems, but I have no idea how big it will get in your tank. I don't think it will be effected by the Hydnophora.

 

[Belladauna]

I guess time will tell. Thanks again.