ID ideas?

[BCOrchidGuy]

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/showphoto.php?photo=339&password=&sort=1&cat=500&page=1

Thanks, Doug

[Jack]

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

[BCOrchidGuy]

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

[Jack]

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

[martym]

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