That is what the medication companies would like you to believe. Ich is virtually indestructable except when it is in the free swimming stage. That is the reason any treatment (salt, heat or meds) must be continued for at least 2 weeks after you stop seeing any signs of it. They cannot be killed once they are in/on the fish and the cysts cannot be killed. Only once they "hatch" and start looking for a new host will they die.Increased heat does work, if you want faster results, you could always get some medication.