I got my biggest loach from a LFS knowing it had itch - the LFS had a Not For Sale sign on the tank, but I said it'd have a better chance to recover in my 10g than at the LFS. So I got it and all I did was the high temp treatment, NO SALT, and water changes along with high air supply. In a week, the ich was gone and he join my other smaller loaches. So the high temp treatment worked for me.
My loaches are doing very well in the same tank with my discus where I keep the temp high at 86F. And it's been like that for awhile now...
I'm glad that the med worked for you. Do you keep your 220g at 75F as well?