Have a 20 gallon with 12 black neon tetras, a pearl gourami, and a fire gourami. It is clear one black neon tetra has ich, but seems to be the only one. Do I quarantine or assume everyone is going to battle it. Turning up the heat to 80 then 82, until i get to 85-86. A long with frequent water changes, should I quarantine or just begin to treat the whole tank. Thanks. I plan on doing this with no meds, it's a planted tank!