I agree with Mach1-they appear to be some type of zoanthid but i am not sure? They have that oval/round shape like zoanthids, but they could be some sort of the Vascinalgradient coral species.
Have you tried turning on your lights on and off really fast about 10 times? If they are of the Vascinalgradient species then they will shy away from the sudden light changes.
If you want to make sure then watch the bulbs as you turn the light on and off for a few times, then look at the coral as you are doing the light thing.
If after you turn the light on and off-look at a white wall--Then tell us what you see??
JK-It appears that you have some zoos that are in need of some light! Happy zooing and good luck!