There is no reef safe cure for ich. The accepted methods are chloroquine, hyposalinity, tank transfer method, and copper. All of these treatment methods need to be done in another tank, or your corals will die.
Secondly, now that ich is in your tank, you must remove all fish and allow the tank to go fishless for 60-90 days to make the tank ich free again.
If you keep the fish well fed and water parameters good, the symptoms of ich may go away, and the fish may do well. Many people choose to go that way. However, as long as there is a fish in the tank, the ich is not gone, it is just not evident. It will come back at some later date when conditions change, the fish gets stressed, or something else.
There are a gazillion threads on the subject here, I recommend you read them.