New fish

Hi I was given a new fish without me knowing as a gift and I dont know about it. It is a longhorn cowfish, tiny little thing. my tank is only 2 months old but all my water tests come out good and dont want him to die but he is acting wierd. he is hiding wont eat and is floating around hit a rocks bottom underneath it.

 

I am taking him back just found out he is poisonous.

 

kind people can unwittingly put is in these circumstances - been there, had that happen to me. (not the same fish type)

what are your water tests? please - and what test kits are you using?

how long has it been in the tank?

what else is in there?

what flow have you got in there? as these species are not great swimmers and can get buffeted about with to much flow (and hit things)

sorry I cant give instant solutions, Id like to be able to but dont have enough information at present

Steve
taking it back is a good idea, did want to suggest it, but as its a gift, felt bad in doing so