ID ideas?
 

Any idea what this is, it's on a rock with some Xenia and Anthelia, it's got tiny polyps like a montipora digitata and it's growing rather quickly, I've had it about a month and there were no spikes on it, as a matter of fact is was about a 1/2 in x 1/2 inch at the time, now it's at least double that size and it's starting to grow vertically.

http://www.canreef.com/photopost/sho...cat=500&page=1

Thanks, Doug

Not sure till it grows a bit more. Hard to tell.

Jack it's growing almost as fast as the calupera around the base... fast grower..

Could be an encrusting digitata but then it looks like it wants to branch out!

It looks alot like my digitata. But mine isn't growing that fast