I am having trouble with my heater. I tried to turn it up to 86 degrees to treat the ich, but for some reason my garbage heater couldn't get over 80. It is a 100watt heater(20gallons) in a 20 gal. tank. So I moved the heater, and my fish over to a 10 gallon quarantine tank to treat them. I guess it is the heat sensor that won't let me do it, but I figured in that small tank, the water would get up to 86 with no problems...but lo and behold, it still can't get over 80... I have a TopFin 100w submercible heater.( ) I don't get this thing's deal, I'm getting a new one ASAP. I guess what I'm really asking, is can 80 degree water effectively treat ich?