Kick ich has only marginal effectiveness at only one stage of the ich parasite's lifecycle. The only consistently effective treatments are hyposalinity and copper.
Garlic Extreme may boost the immune system of the fish and stimulate the appetite. I would consider using this along with hyposalinity. Garlic Extreme is difficult to pour out of the relatively large bottle without having the oil drip (and releasing its pungent odor). It probably works best by soaking your food in it.
With the usage of these products, some fish are able to develop a limited immunity to ich. However, the ich parasite is still able to reproduce in a limited fashion. If you add new fish to such a tank later on, they will get ich and have a potentially severe disease. The best thing to do is to fully treat the disease and set up a quarantine tank so that this does not happen again.