here's another pic, sorry these are the best of the bunch and it's a borrowed cam so...
More info:
What I'm trying to ID is the whitish areas that make up about 30% of the rock, it is made up of individual plates (kinda looks like an inside out soccer ball, with the seams being the joints between the plates) The plates sometimes open up and I can see feeder filaments between them. I've been told it's probably a tunicate on another BB, but I more opinions are welcome. It is doing well so, I'm not all that concerned as I haven't done any direct feeding and it is still doing well.