Got a new male mandarin 2 days ago drip acclimated him and he was doing well very lively in the store and after release found him today very sluggish on the tank floor noticed a fin had been nipped. I am guessing someone did not like him being introduced. Put him in my new 75 gallon tank down in the refuge he is just laying there I hope recovering but I know this is going to sound strange but it looks like he developed a cough cuz he will breath fine and then exhale real hard blowing the sand in front of him I have sat and watched these guys and never seen them do it. Should I be worried for the little guy if so what can be done that I haven't down.