Water from the public water supply networks varies in hardness depending on the region.

During its natural trip, water dissolves carbonates from rocks through which it flows.

Water is then loaded with carbonates and magnesium salts.

 

Water softening is a procedure which substituts the ions which increase the hardness (carbonates and magnesium) in water with sodium ions in a process called ion switching, creating salts which are more water soluble and stable and do not create deposits.