I don't have a reef tank but . . .I would be very cautious in adding any medications to a display tank, especially a reef tank. Generally speaking, it is very difficult to treat ick with any kind of medication.
I had ick hit my FO tank, and the only thing that stopped it was a hypo. They do work. And after this experience I went out and bought a second tank as a QT.
Ick is a parasite that requires a fish to live, although part of that time is spent away from the fish. The only way to rid a tank of ick is to break the cycle. (The only medication that is really efficient is copper, which is also bad for fish, and deadly for inverts!)
Inverts also can't survive a hypo. Do you see where I am going with this?
Just because one or two of your fish have ick does not mean rest of the tank is okay.
And if you have inverts, you can't do a hypo.
To really get rid of it, you are going to need a second tank.