Like novice said, this one is for aquarium salt (or some similar salt). Honestly, salt baths have a limited effectiveness against fungus. You can try it though. I do not know the dosage off the top of my head.
You can also try swabbing the area (out of the water) with hydrogen peroxide and removing any fungal growth with a tweezers. It is invasive, but if you can do it speedy it isn't a big deal.
General cure will not likely help you.
Frankly, I dislike melafix and pimafix because they are low dosage and have a very limited effectiveness so I rarely recommend their use. Since you already have them though, you could go ahead and try a mela/pima combo treatment and see if it helps along with clean water. Pimafix is the one that is said to sometimes help with fungus, so if you want to use those, I wouldn't do the melafix alone.
The tetracycline will help for the overall infection and the sores that seem to have formed if you want to go that route and would be more beneficial than the general cure for what seems to be going on. The ingredients in general cure are by far best at parasite eradication, not so good at bacterial issues.
