Minerals and salts that dissolve in water form ion’s. Deionization is the process of removing these salts from water. Deionized water does not conduct electricity and its purity is measured by resistance to carry an electrical current. Systems and filters are available to produce water between 20 kilohms and 18.3 megohms. Deionized water is useful in such applications as laboratory water, spot free rinsing, Aquariums, Battery Filling and humidification to name a few.