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Water Treatment Technologies
Different Treatment for Different Problems

No single water treatment technology is effective in treating all water problems, which can range from scale-depositing hard water to disease-causing organisms like Cryptosporidium. Specific technologies are applied to meet specific needs, either individually or in combination. Equipment using the various water treatment technologies is applied at the point-of-use (POU), such as the kitchen sink where water is actually drawn for drinking or cooking; or at the point-of-entry (POE), where water enters a home or business. 

Water Filters
In a conventional filtration system, water passes through a filter media, such as a solid block carbon filter (usually a cartridge in smaller units) , which either adsorbs or physically screens out various contaminants. 

Reverse Osmosis (RO)
Reverse osmosis systems pass water through a synthetic, semipermeable membrane that rejects most contaminants. Virtually all RO units have carbon pre- and/or post-filters to provide additional treatment for health-related contaminants. 

Distillers heat water in one chamber and turn it into steam. The steam then passes from one chamber to another, where it is condensed back into water. More than 99 percent of aesthetic- and health-related contaminants, such as lead, some heavy metals, bacteria and cysts remain in the heating chamber. 

Water Softening
Water softeners use the "ion exchange" principle to exchange ions of either sodium or potassium for ions of hardness minerals (calcium and magnesium) present in the source water. Some health-related contaminants also can be treated, such as radium and low levels of lead. An offshoot of this technology using "anion exchange" reduces arsenic, nitrates, and mercury. 

Oxidizing chemicals like chlorine, bromine, and ozone are added to water through a feed system that controls concentration and allows appropriate contact time. These chemicals neutralize aesthetic organic contaminants in the water and also kill a variety of biological pathogens. 

Ultraviolet (UV) systems use ultraviolet light to eliminate various biological pathogens. 

Aerators temporarily store source water in a tank to allow easily evaporated volatile contaminants to be vented off. Air can be bubbled through the water to speed the evaporation process. 

The performance of equipment can vary, so it is important to look for products tested and proven to be successful for the specific contaminant(s) to be treated.