You can prevent hard-water problems with water treatment or filtration. The presence of large amounts of calcium or magnesium in a water supply makes the water “hard water”. When these are removed, either by filtration or some other process, the water is called “soft”. Hard water can cause a lot of problems including build-up on showerheads and faucets and the inside of pipes and filmy soap scum in showers and sinks.
Reverse osmosis systems can be used to remove the calcium and magnesium from the water, but to use an RO system for a home’s entire water supply would be very expensive. That’s why many people choose to install a water softener in their home.
The idea is to replace the calcium and magnesium ions with sodium ions, which do not cause the same problems. The tank in the water softener is loaded with tiny beads called zeolites. These zeolites are so densely covered with sodium ions that when water from the home is forced through the tank, the ions trade places. This means the calcium and magnesium “problem”-ions are now stuck to the zeolites, leaving sodium-charged soft water to flow through the home’s pipes.
Eventually, the zeolites become thickly so covered in magnesium and calcium ions that the softening process becomes ineffective. At this point, it’s time for regeneration. Since rock salt is composed of sodium chloride, it is used to supercharge the water in the tank with more sodium ions- so much more that they replace the magnesium and calcium ions on the zeolites. The remaining water is then flushed out through a drainage pipe and the softening process continues.