I have a 90 gallon tank. FOWLR and snails and hermit crabs. I've had it for 3 years. No problems until I recently added two new fish without quarantine (stupid, I know). I have a blue tang which I have had for about 2 years with no problems. Now a huge ICH problem. Salt all over her. And now my puffer is getting it too. Second stupid mistake--I treated the main tank. 10 days of RidIch so far. The ich is still on my fish. What do I do? Please help!