What are the main ways to soften water?

Ion exchange. Ion exchange is the oldest and most common water softening method. As a rule, it involves the exchange of magnesium and calcium ions contained in solid water for sodium ions. Since each calcium and magnesium ion has a positive charge of 2, each ion is exchanged for two sodium ions.

Distillation. Here, the water is heated inside the container until it evaporates. This steam is then fed into the container with a cooling device through a tube. Then the steam condenses, returns again to a liquid state, water.