I use pickling salt from the grocery store for torn fins and injuries, not on a regular basis though. picking salt is cheaper and does the same thing. I also use epsom salt to clean out my fish and to increase the water GH or hardness
i will add 200gram of salt for 50% of water change for my 120G tank..my fish just fine with it..disease also not accour..there are 1 asian arowana, 1 florida gar, 2 Buttikoferi, 3 red crayfish, 1 red eye albino senegalus birchir and 1 polypterus delhezi.