All of my fish in my twenty gallon died. There were 3 cories and 1 gourami. The cories died first, when they died there skin(slim coat i think) started to get white and cloudy and i think it stated to raise. I thought the gourami was good but I couldn't see the skin thing because of the pattern. The temp was at 78, The filtration is a ac30,a powerhead (94 gph), and java ferns. Not sure about ammonia,nitrikes, and nitrakes.