Maybe Ich?

[justinl]

cleaner shrimp are hit or miss with parasites. DO NOT get a cleaner wrasse. these are one of those fishes that don't even belong in the fish trade. they eat parasites well, which is great but that is ALL they eat. run outta parasites (easily done in a glass box) and you run outta food. fish dies. it happens all teh time with maybe one in a thousand surviving by eating frozen.

you want a fish that will pick at parasites? get a couple of neon gobies.