Sodium chloride (salt) is the main ingredient in water softeners.
Not to argue, if we're talking about a water softener, not "Calgon", this is a common misconception that is a logical progression from seeing the salt bin that sits next to the typical domestic water softener. The only component in water softener tanks is a plastic resin bead. If you've ever seen dance wax, that's what it looks like. Tiny plastic balls by the gazillion. They are the medium responsible for the ion exchange that makes the softener work.
Very basically, the plastic beads exchange calcium, magnesium and some iron ions, removing those undesireable minerals from the water. In the process, they release sodium ions that are not objectionable. When the beads have reached their capacity, the exchange stops, they're no longer effective. To regenerate the media, it's slow rinsed with super saturated salt brine, and the exchange occurs again, except the magnesium & calcium ions are exchanged for sodium; the magnesium and calcium goes down the drain, the sodium ions stay on the beads. The final rinse removes salt residual from the media so the water's palatable. The process then repeats until the next regeneration cycle.
That's why there's always salt involved with softeners. The water doesn't flow through the salt other than to keep enough reserve in the brine tank to make the brine. And, no, softened water doesn't taste salty, it doesn't contain salt, only the sodium left from the ion exchange. And yes, it does bump sodium levels, but hype about sodium levels and softeners relating to heart issues has pretty much been proven to be of no consequence.
