I've got a demasoni who's been hanging around the tip corner of my tank a lot but still swimming around. I think it's being picked on but I'm worried that it might actually have a disease. I separated it from the other fish yesterday in a hatchery but it looks worse. It's losing colour in the back half of its body and seems to be turning white on its underside but it doesn't look fuzzy more like pigmentation. All the other fish seem fine. Parameters are ph 8, nitrate & nitrite 0, ammonia 0. It's a 165l tank with 2 demasoni, 2 peacocks, 2 maingano, 2 red zebras, 2 cobalt blues, 2 electric yellows & a bristle nose.