Date of this Version
The presence of calcium (Ca) and/or magnesium (Mg) in water results in water being considered "hard." Calcium and magnesium ions in water react with heat, metallic plumbing, and chemical agents such as detergents to decrease the effectiveness of nearly any cleaning task. Hard water can be softened using an ion exchange softening process. This 2008 guide discusses the ion exchange water softening process and related equipment used for household water treatment.