times10. I am far from an expert. Believe me but I am currently using the heat method to clear up a slight Ich I caught quickly. It seems to be working great. I am a naturalist and do not like to add any chemicals to my tank.
I have 13 live plants, all pretty new and they are dealing fine. My fish donot seem to mind the 90deg water at all. Like I was told (Zagz actually) and read everywhere: Warmer waters retain less disolved Oxygen so lower your water level if you are using a HOB or get an airstone.
Again I AM NO expert. But I just though I would share my experience to add some confidence to your dilema. Heat works well.