I am gonna go a different way than ouling here- while the feed suggestions he mentioned have been anecdotally mentioned to work, there are surely not guaranteed or quick.
I also want to strongly caution about copper usage. Copper is toxic, even to fish at high enough levels, so I hope I am reading Oulings post wrong. Definitely NOT the more, the better. If you use copper, use it exactly y the dosage recommended, and buy a copper test kit.
Brandon has a number of excellent posts on this forum of accurate and beneficial ways to treat ick, just find one of them.