I could be wrong or the species may not be right.but i saw what i thought was a very cool looking fish at my lfs and it was called a rainbow wrassie as well.i came home and looked it up on a few different sources,and learned it was one of the worse fish you could put in a reef tank.due to there eating of corals.to help with building ocean reefs.
if yours is really a rainbow and has not eaten your corals,than you may be lucky or it's only a matter of time.But every fish is different.heck knows i've had some change.
look around on the web and see what kind of info you can find and compare picks of yours to the real thing.
