One of my members at BP forum wrote this when dealing with Ich, hope it helps.
Quote:
Ick appears not to be able to survive temperatures above 82F. By raising temps to above 82F one can kill all the parasites; generally, 5-7 days after the temps have been raised above 82F you will see a reduction in white spots on your fish. It is best to continue a stable temps of above 82F for at least 2 weeks to ensure all the parasites have been killed. Do not raise temperatures too quickly. 1 to 11/2 degrees F every 12 hours is best, although if you keep your temps very low you may need to shorten that to 1 degree F every 6 hours. Raising temps too quickly can stress fish. Keep in mind, Ick multiplies more quickly at higher temps below 82F; it is necessary to find a balance between raising temps slowly enough not to stress the fish and quickly enough to keep the fish from becoming too infested with the parasite. Also, be sure all the fish/invertebrates in the tank can handle temps that high. Adding salt at the rate of one round tablespoon to 5 gallon of water. (do not add salt to a cory tank) In case if your'e not sure, do some research and ask.
I find this methods works great for me.
Warning
**High temps reduces the amount of oxygen in the water. Increasing surface agitation, either by lowering water levels if one has a hang on back filters so the water falls further, or adding addition aeration with a airstone is recommended. Machalite green treatment at a half dose with high temp will help relieve an already stressed, ick infested fish. Do not use machalite green at full dose for cories, loaches, catfish or scaleless fish. Be sure to remove carbon(the black small rocks) from your filters.
