get some furan 2 powder. mix it with tank water till its like pea green in a bag or bowl.. put your frags in there for 20-30 min. repeat for 4 days. then take 3 day break. then repeat dips again for 4 days and break for 3. then repeat for 4 total weeks.
Rinse in fresh water too, it pulls the excess chemicals out of the zoa tissue better than just placing the coral back into salt water due to osmotic pressure.
Also, the fungus tablets made by jungle often sold at walmart work just as well. 1 tablet per 1-3 cups is the excepted dosage range, but 1 tablet per 3 cups works fine. Good luck.