Hi, I don't suppose you could post pictures of these wounds, could you? That would help with the diagnosis because just from the description, they could be a lot of things. Wounds, columnaris, ulcers, missing scales . . .
Kosher salt is good but when you can, to be on the safe side, pick up some AQ salt. It's cheaper too. Don't want to use up all your good cooking salt.
When treating with salt in a 1g tank, do 100% water changes every day and redose the salt. Don't add in salt every day because salt doesn't evaporate so you'd just be building up lots and lots of salt and eventually, it would reach toxic levels.