Kick Ich will not have completely killed it, cgoodman is right. In fact, using the medication in your main tank was a bad idea. No medication for ich is completely reef safe, and you may have compromised any inverts in your tank and the bacteria on your live rock. That's why you should ALWAYS medicate in a quarantine tank, never in a display tank. Some medications will say they are reef safe, but it still seems that about 50% of people that use them have their inverts and corals die off.
Copper and hyposalinity are the only two methods that have been proven to kill ich. Try anything else and it will probably keep coming back until you find and eliminate the stressors in your tank.