yeah he should definitely heal up just fine, i wouldnt even worry about salt its not that bad just keep water clean, and good diet is pretty much any more commonly known brand of pellet specifically designed for cichlids supplemented with fresh/frozen stuff like insects and shrimp maybe 3x a week or so (i dont even supplement this often, i mainly feed just pellets and my fish heal fast if they happen to get any tears in their fins, but it wouldnt hurt to beef this guy up a bit) GOOD LUCK with him