Water Softeners
All water softeners work the same way by removing the magnesium and calcium in your water through a process called ion exchange. Adding salt to the water softener allows the resin bed to regenerate (clean it's self) this is done automatically.
Water softeners are either powered by electricity, batteries or water pressure.
Water Conditioners
A water conditioner works to temporarily change the chemistry of hardness particles, resulting in a reduction of scale build-up in plumbing, for a certain amount of time.
