yes. kosher, iodized, rock, evaporated sea salt, whatever kind. As long as it's NaCl and not like epsom salt (MgSO4). I use table salt, iodized because I couldn't find the non-iodized kind. Don't worry about the iodine, there's so little of it that your fish would be "pickled in brine" long before the iodine would hurt them. I prefer the table salt to "Freshwater Aquarium Salt" because it's cheaper and the smaller grains dissolve much easier.
Just make sure you dissolve the salt crystals in a separate container BEFORE adding it to the tank. If the salt hits your fish, it will burn their skin and gills.
Just make sure you dissolve the salt crystals in a separate container BEFORE adding it to the tank. If the salt hits your fish, it will burn their skin and gills.