The tank should be kept at 87'-88'F and salted at at least 1tblspn per 5gal, this will eradicate any ICH and some parasites.
Raise the temp slowly (degree or so each hour) and add the aquarium salt slowly (mixed with tank water) over the course of several hours to a day or so.
Do daily gravel vacuums to remove any Ich cysts from the gravel.
When replacing water, only replace the salt according to how much water you are putting BACK into the tank.
Keep the heat and salt up for 2 weeks PAST the last sign of ICH.
It is critical that heat exceeds 86 degrees. At 86 degrees or less, it will only serve to speed up the Ich life cycle, making things worse. Increasing the heat will cause a sudden "explosion" of Ich cysts on your fish. This is expected. These are Ich parasites that are already embedded in your fish. They cannot be killed once they reach this stage. It is only when they fall off into the gravel that the heat/salt treatment (or medications) can become effective by preventing that single cyst from dividing into hundreds more, and by killing free swimming Ich looking for a host to land on.
Ich that has already found your fish cannot be killed and Ich can be embedded in your fish for weeks before it becomes visible.
Ich can only be killed in it's free swimming stage. By increasing the temp, you are lessening the amount of time the Ich will remain on the fish.