Stop treating with Rid Ich. It's effectiveness is questionable at best, and its long term effects on reef tanks can be undesirable. For instance, I saw a tank treated with rid ich. It had some coral, fish. The mushrooms all bleeched out [lost there color].
If the tank is fishless for 3 wks after the removal of the infected fish, then the tank should be ok. However, if you remaining fish were exposed to ich, they should be treated before returning them to the display.
Hyposalinity is the best method for treating ich. If you want info on hypo, there is a post on the subject in the FAQ section.