Microbe-lift Artemiss??

[tcwells23]

I think my clownfish has mouth rot, however, I'm not completely sure. It started out with white fuzz on its mouth. Now it is grey and the tissue seems to be rotting away. My LFS sold me Microbe-lift Artemiss and said they use it in all their tanks. It is herbal and is an immune booster to help the fish get rid of the disease. Does anyone have experience with this...does it work? My clownfish is unable to eat because the mouth is stuck open. This is day six since this started. I don't know if I should try to catch it and move to QT and treat with an antibiotic or continue to use the Artemiss. Also, my other clownfish has developed the white on its mouth too. They are the only two fish in the tank. Any help would be greatly appreciated.