Hello. I have 2 tanks that i use the same syphon for. All the sudden, both tanks are showing symptoms of disease. My 20 gallon mollie tank has 2 out of 10 fish with brand new white spots. In my 120 gal, My rhombeus Piranha’s left eye is half white. I have raised the water to 80 degrees and added salt. I cant use mechilite green on the piranha. I have read that is is lethal to them. Please help