Not advisable to use it every day, i'd say use it after a weekly water change. thats once weekly. the only way dissolved salt leaves the tank is through water changes. If you add too much salt your water will become brackish, and then the equivalent of marine water as more is added. It all depends on what youre keeping in the tank.
Its important to use the directed amount once during the initial addition of tap water to the tank. then the salt should only be added once weekly, the amount depending how much water your change out.
I have salted my 2 year old betta when i was young and didnt understand salt correctly. the beta died of course, so please dont add too much for your fish.