Hello today i brought a red devil fish and he is white atm he is really big and i have a 40gallon fish tank i am only going to be kept him in there the pet shop told me he is a really hardly fish is this ture ???
The Red Devil is a hardy fish, and is typically one of the most aggressive. A 40G tank is too small for a RD. You might be able to keep it there to grow it out, but it won't survive in there long term -- and most of its tank occupants will probably be picked off long before that.