I have a 5" geophagus that the center of his eyes has turned cloudy. You can see a black ring around the cloudy part and the lens covering the eye is clear. My fish guy thought it was eye cloud so I treated it with Melafix for two weeks with no change. None of the other fish in the tank have this and the fish seems healthy otherwise and does not bump into things and seems to see me. Could this be catatacts? Do fish get cataracts? If it is not cataracts what could it be and how should I treat it?