Im sorry, i dont know very much at all about marine stuff, so any advice i gave could do more harm than good. But could you give a little more information please, so when one of the saltwater guys looks at it they have something to go on. Some of it may not be relevant, im just cutting and pasting the questions from the SW
sick fish sticky.
How long have you had the fish? Do you know if it was wild caught, or tank raised?
How long has the fish been in the tank? What are the tank mates? Any aggression?
Is the fish eating? If so what does it eat?
What are the water parameters? pH, ammonia, nitrite, nitrate, SPG? (actual numbers please: posting high, average or normal is not helpful) What saltwater test kit are you using?
Is the fish showing any physical signs of disease, grain of salt size spots, discoloration, ragged fins, misting or spots on the fins, cuts, cloudy eyes, etc?
Is the fish "flashing" (scratching or rubbing on rocks, decorations or substrate)?
How is the fish acting? Is it swimming around, or just hovering in one spot or corner of the tank?
Did you use quarantine? If so for how long and did you have a need to treat for any ailments? Is it in*qt*now? Are you currently treating with any medication(s)?
Describe in detail how the fish was acclimated.
What size system? What type of filtration do you use? Do you have any live rock or sand?
Do you use any additives? Have you used any sort of meds in the main tank?