A saltwater treatment system will cost about $1,200 to $1,400, but will pay for itself in a couple of years by not having to buy chlorine products. It’s not salty like the ocean, more like a salt-treated water softener, one tablespoon of salt in a gallon of water. The system works by a current separating the sodium chloride from the water in the filter system to sanitize the water. The molecules re-assemble so you do not have to add salt unless it rains or water is added from the hose. There are other systems that use natural mineral purification, ozone gas and bromine, but they only reduce the amount of chlorine you need to add.