They are prepared to supply soft water to an exclusive house and have high flow rates. In an ion-exchange method, a resin inside draws calcium and magnesium ions from your water and returns them with sodium ions. When your resin heads out of positively assessed sodium ions to trade for the hard minerals in your water, salt can be used to restore it. This will necessitate some regular care on your part, as renewal will need to happen about one time in 7 days (a week)