Soft water

Soft water is water which has relatively low concentration of calcium carbonate and other ions . It contains less than 85.5 parts per million of calcium carbonate.

The water that lathers with soap easily is called or known as soft water. It describes

of water that contain few or no minerals like calcium (Ca) or magnesium (Mg) ions. The term is usually relative to hard water, which does contain significant amounts of such ions.

Soft water mostly comes from peat or igneous rock sources, such as granite but may also come from sandstone sources, since those sedimentary rocks are usually low in calcium and magnesium.

Hard water may be better for the heart than soft water. Its calcium (Ca) and magnesium (Mg)ions may be a dietary supplement for some.

The main disadvantage of hard water is it deposits calcium carbonate on pipes, especially hot water pipes. This is called "scale formation". It may cause blockage of pipes and reduce boiler efficiency. Also, soap and detergents work less well in hard water. These effects increase as hardness increases.

Soft Water Media

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  A bathtub faucet with built-up calcification from hard water in Southern Arizona.

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  A portion of the ancient Roman Eifel Aqueduct in Germany. After being in service for about 180 years, the aqueduct had mineral deposits of up to 20 cm (8 in) thick along the walls.