I have a 10 gallon tank that is currently home to two congo tetras, a dwarf gourami, and a flying fox. I've had the gourami for about two months now; he beautiful when I bought him, but over the past few weeks he's been looking sickly. His colors are faded, fins are clamped, and looks like he's lost weight. He's still eating and swimming alright though, and on top of that, the other fish in the tank all continue to look perfectly healthy. Any help would be appreciated!