we have a a 900g filled with fish. An assortment of gangs and several angels. Several days ago the korans eye was cloudy and is getting puffy. Looks nasty. Well today our large sailfins eye looks cloudy to. Getting these fish out of this tank will be next to impossible. What is the best road to take. Water quality is perfect, I hoped it was just isolated, I really hate treating the whole tank, seems like usually ends up doing more damage than good. Help!!!