As it reads I have a 4 inch RTC (not my first I have 4 or 5 bigger guys) but I have never had this happen he is in a grow out tank (55 gallons) with a 2 inch red devil and a 3 inch hybrid flowerhorn all are doing well besides some ich which has been addressed with salt and heat I did 1 table per 5 gallons to try not to hurt the catfish and it usually works out for me and I last night I fed him so tailpa cuts while I was feeding the bigger fish in my other tanks and he ate fine he was super fat afterwards so I left him and I come back out now and he is shaking and trembling anyone know what it is?