Since no one seems to have mentioned it... if you have some sort of substrate in your tank, be sure to vacuum it VERY WELL to get rid of any remaining ick in the tank... the last thing you would want is another outbreak once you fixed it...
I think thats a lil overkill especially the 90 degree temp. I never go over 86 and of the few times my fish have gotten ick it only last a a few days at the most