I have had good luck taking care of ICH with salt and high temps. I am by no means an expert but here is what I do. SLOWLY raise the temp to 85 and add 1 tablespoon or so aquarium salt per 5 gallons of water. I do frequent small water changes making sure to add salt to the replacement water. Within a couple days most of the ICH should dissapear off the fish. From the time all the ICH is no longer visible on any fish, keep the temps up for another 2 weeks to kill the ICH thats still in the water but not on your fish. Do not forget to do several large water changes after the 2 weeks to remove the salt and gradually bring temps back to normal. Now obviously many plants and fish can not take the salt or high temps that long but that is a general guidline that has worked well for me in the past. The only fish I've lost from doing this is a single giant dannio. Even my pictus cats and clown loaches have survived. They sure as hell don't like it and are not very happy during treatment but always pull through.
edit VERY Important, when raising the temps your lowering your oxygen level in the water. I put my airstone(s) on max and lower the water level (makes filters more like a waterfall) to increase aeration and helmp combat the lower oxygen levels of the warmer water.