I have had a few....they have never caused any problems to my corals, clams, or crabs. They also have not stayed in the tank.....no matter how narrow the opening, eventually they find it. Expect it to disappear for the first 2 days....when first introduced, they frequently bury in the sand. then they appear for an hour or two...after a few days they are out all day and acting normal. I have no wrasse at all now...also no pyramid snails. I haven't had the ones that feed on clams in many years. I used to have the smaller ones that sit on Astrea's. (I sent some to Ron Shimek, who assured me that they were of a different species than the ones that attack clams..), but none of those anymore. They killed all my bristleworms too...I was glad to finally see one again...they are great scavengers. Wrasses (not just the yellow ones) eat them...they also compete against mandarins for food......
