I had a flower horn that got duck lip, and I actually got the fish back to health by using Melaleuca oil directly on the fish. I removed the fish from the tank, held it in my hand, and rubbed the straight Melaleuca(not Melafix) directly on the mouth of the fish. I did this twice a day for a week straight. I kept the fish in a tank with both Melafix and Pimafix in it at twice the recommended dose. The disease cleared up but several months later it returned and was causing the fish to thrash its head against the glass and rocks. I had to euthenize the fish, as the treatment didnt work the second time, it was suffering.
Anyway, you could try the straight oil, I got it from a hollistic shop that sells herbal extracts.
Anyway, you could try the straight oil, I got it from a hollistic shop that sells herbal extracts.