I bought a Panther Grouper (about 3 inches) this past weekend and he jus sits at the bottom of the tank all day. He has eaten a couple live fish since then, so eating and catching good is not an issue. He just doesn't swim. There are 3 other fish in there with him... Narrow lined puffer, volitan lion, and spotted grouper. All about same size with the lion being the largest but doesn't mess with anybody. Tank has been set up for a while and the other fish swim normally. He tries to swim, but always just sinks to the bottom and lies there. Any information you could provide would be great!
It's in a 140 gallon aquarium made.