Well maybe not. Looks like a little Pocilliopora growing out. Not put there on purpose, I have a few of these growing around the tank. The cool thing is that the pocilliopora colony that this came from is in my frag tank.......and it has been in there for a long time. It is sitting right next to my gravity drain on the frag tank. Must have went down the drain, through my circulation pump and into the main tank.