No..Melafix is not a stronger version of Bettamax. Bettamax is a med . Bettafix is the weaker solution of Melafix. Neosulfex was the best I could find for finrot, but I can't find it anymore. Tetracycline is good for it too. Try a salt bath. Either continue the bettamax, or try tetracycline, or another med for finrot.