A Water softener is the most effective system to get rid of lime/scale out of water.
It contains resin on the inside of a cylinder which receives the excessive lime and magnesium minerals present in water. It has to go through a regenerating process (similar than a swimming pool’s sand) in order to prevent the resin from becoming saturated with lime/magnesium minerals. Coarse Salt has been found to be the most effective way of cleansing the resin from the accumulated Lime/magnesium minerals; therefore it is a very cost effective system in the long term because of the low prices of salt. Water softeners can function in both low (gravity only) as well as high water (pressure pump) pressure. See fig below:
A water softener normally have a very long working life and is designed to be used in our South African weather and climate.