Everyone trust the lfs owner.. they know all not.... reef safe could be in a matter of opinion but i tell you my reef better be REEF safe for ALL critters withing... green brittles no matter how they are looked at are destructive.. no they wont eat a coral but when they get 24" across they sure can plow them over... other than that... there are black brittles (wich hide 90% of there life under a rock or behind the rocks) and make awesome REEF safe additions.. also there are many types of serpent star that are REEF SAFE additions... if you look at the generaly consensus of the post and replys.. green brittles are not a good addition to a community tank.. but im sure if sumone would send them all the the LFS they will make a nice community tank of green brittles.. till they start eating each other... hmmm 