I have an adult angel with cloudy eyes some fin and tail rot no appitite and a 2" or so loss of color band in the center of his body. He also twitches and rubs his eyes on rocks. I was away for two weeks and had my son take care of the fish. Nitrates had rose very high and it took two changes a day apart to bring them back to even the high side. Was it the poor water quality or something else. Thanks, Bob