My wife did some research on this. The water is drinkable. The ppm is low enough not to hurt you. The water may actually be cleaner than your tap water. Actually about the same amount of salt as Gatorade. So, I have a 10,000 gallon supply. Because of rain, I have to add salt about every 2-3 months. Also, the clorinator makes clorine out of the salt. When it gets back into the pool the clorine recombines with the sodium to make salt again. This is a continuous process in a salt water pool. The pool pump runs 24-7. It is constantly being filtered, clorinated, evaporated, back to salt, then back through again. This is how it remains clean.