seabird wrasse eating snails/crabs?

[dakar]

this was an up and running tank, i recently moved the tank to my house (this past saturday). the fish guy to just keep him under observation as he might just be stressed from the move.

Very likely what we call 'shipping stress', tangs are easily stressed.

I'm not perticularly fond of the wrasse, he hardly comes out from under the rocks, if i take him to the local shop will they usually trade for different types of fish?

Most of the respectable LFS's will give you some sort of store credit or exchange for healthy animals... The larger chain type of shops generally tend not to do much of anything in the way of helping.