Ashley,
This thread is about an age old problem EVERY saltwater aquarist/hobbyist encounters at one time or another. I've used that "No-Ich" medication that you're using. It does work...to an extent. HOWEVER, you have to do a number of things. I've also used "Ich-Attack"; just as effective. First, you have to leave your skimmer off and remove your carbon. These are options that many of us are leary of. The meds work but are not very good options b/c they're not 100% effective and even if you are able to treat the tank with success it will have cost you TOO much to be worth the effort. NO-Ich is EXPENSIVE! And there's no guarantee to it.
Every hobbyist here and in other forums will give you similar advice and most will have nothing to do with harsh medications. The most EFFECTIVE way of treating this age old parasite is to CATCH THE FISH and quarantine it/them. A 30 gallon should suffice for this purpose; lower your specific gravity/salinity (gradually) over a period of a week until it's approximately 1.008 (use a refractometer; it's more accurate). Let your tank go fallow for a period of no less than 4 weeks (month) meanwhile your fish are being treated by hyposalinity during this same time frame. This method kills two birds with one stone (so to speak); actually it's more like, killing one parasite with two methods.
This works. Your inverts/corals should be fine in the tank by themselves since cryptocaryon does not survive without a fish host. In addition to this, I recommend...no I INSIST you do some research on the cryptocaryon irritan protozoan parasite. Understand the biology of the life cycle and what must be done in order to annihilate such a horrific pest.
Good luck.