I recently purchased a white spotted toby from the LFS
and have had it just over a week. It is in my 180l tank with a maroon clown and blue/green chromis and to my knowledge none have been showing the others aggression. It has been eating well since it has been in the tank being fed mysis and krill. The nitrates are 10-25, ammonia 0.1 but unsure o the other parameters as I haven't got a home kit for those (I did a 10% water change today).
The fish looks like it has slight discolouration (pale patches) near the tail but doesn't have signs of ich or cloudy eyes. It is still swimming actively and only temporarily pops in a cave for a hide. I do have sand and live rock in my tank.
I haven't got a quarantine tank and have refrained from adding additives and meds to the tank as I didn't want this to make things worse.
Any advise on what this could be or how to treat I would be very grateful.