I bought the geophagus a few days ago and i noticed one of its eyes is messed up. The eye is sunken and cloudy, it almost looks diflated. It is swims around but tends to hang around in one area. It is eating but its seems more aggressive to the other fish in the tank. it may be a little more sluggish then the other fish but not by much.Its either a disease or a wound from when it was in the tank st the store, anyone know what it is?