Regarding the cleaner wrasse, I feel that it is more than just failure to sustain them in captivity. That is the other down side of keeping them. The real impact is that fishes in the wild actually depends on these fishes to keep them free from parasites. Over collection of the cleaner wrasses may result in more fishes in the wild succumbing to parasitic infections. Besides, there are other fishes or shrimps that can perform the same role (cleaner shrimps, neon gobies) in our tanks. Anyway, if you really want to get one ... don't get those multicolored ones. Some reefers do have success with the common cleaner wrasses (the blue ones)
Just to clarify that I am no expert here but I read the above somewhere (possibly wetwebmedia.com) and just to share. And definitely no offence to bro Jervis or anyone ... even Henry (in my opinion, a very respected reefer ###### LFS owner) keeps a cleaner wrasse in his display tank ... and very successfully too!