How much total salt did you add? Increasing salinity should be done gradually--adding the full amount of salt all at once can stress fish. It should be done over time, by adding a portion of the total dosage to a jar of tank water, dissolve, and then poured in. Wait an hour, add another portion.
Also--adding salt and a medication--not good. Melafix can cause low oxygen levels, and heating the tank in addition reduces the amount of O2 the water can hold--serious problem, especially for bottom dwellers.
Your best bet for now is to test salinity, maintain the heat, and start doing water changes. The heat alone will kill the parasite, and the water changes will gradually get the water back to 'normal'. Mixing treatment methods is not advised, as medications can and do react with one another, causing worse problems than the original symptom you were treating.