He has been with me for about 2 months. No other sick fish in tank. He isn't eatting and appears bloated. Has become washed out and stays at the bottom mostly hidden, also looks a little pineconey. Has some darkening around gill area. water= ammonia 0, nitrite 0 and nitrate 10. I have tried a variety of foods/ No one is picking on him/ lost other one within 2 weeks of purchase. No sores on him. But doesn't even look at offered food. Any other symptoms I should watch for? If he has it I know there isn't anything I can do. I don't think it's dropsy. I change water 25% about every 4 days. Sometimes up to 40% Dwarf rainbows breeding. neons seem happy. corys playing. otos doing their thing. tank seems good. Just the gourami.