Whole-house water treatment systems range from simple canisters with disposable filter cartridges to complex systems of tanks and filters for different contaminants. A system that includes a water softener may be bypassed by a cold drinking water line to provide salt-free drinking water. Whole-house systems are typically installed immediately downstream from water meters and well pumps, and thus may be referred to as point-of-entry (POE) systems. Depending on the filtration and treatment processes, they remove or reduce iron, sediment, chlorine odor and taste, and other chemical and biological contaminants. In doing so, they help protect plumbing and fixtures, reduce unpleasant tastes, colors and odors; and, in some cases, provide healthier water. Regular maintenance of a whole-house water filter system may be as simple as replacing a filtration cartridge every six months, or may require an annual service call. The initial expense of a whole-house water filter system often pays off in the long term, as it may protect pipes and fixtures from iron and/or hard water deposits and discoloration and provide savings in bottled water costs.