- Water softeners usually consist of a tank in which water is pumped through plastic resign beads that are covered with a sodium or potassium salt. The sodium or potassium on the beads is exchanged with the calcium or magnesium in the water. The "softened" water is then sent to fixtures throughout the home.
- Over time, the beads in a water softener become completely covered with calcium and magnesium, making them no longer effective in ion exchange. The beads need to be soaked in a brine solution, flushing all the calcium and magnesium down the drain. The beads are then regenerated with sodium or potassium.
- Although water softeners are primarily used for calcium and magnesium, water softeners can also remove up to 5 mg/L of dissolved iron.
- Water softeners can reduce soap scum and scaling on fixtures. Softened water also produces more soap suds, leading to better cleaning of clothes and dishes.
- Softened water can feel slippery or slimy. Many people do not like the feel of softened water or complain that they feel as if soap doesn't completely wash off their skin. Homes with a water softening system may go through more water heaters over time as the salt can be corrosive on the heating coils.
