In many parts of the country (including mine) the water contains high levels of dissolved minerals and is commonly referred to as hard. Groundwater very slowly wears away at the rocks and minerals picking up small amounts of minerals and metals that can be a nuisance in elevated concentrations. Calcium and magnesium ions are the minerals that make water hard. Before considering purchasing any treatment system test your water yourself to get a full picture of the nature of your water supply. No treatment is without cost or consequences and an inappropriate treatment could create other problems.
Water containing approximately 125 milligrams of calcium, and magnesium per liter of water (ppm) can begin to have a noticeable impact and is considered hard. (Some label water hard at 100 ppm.) Certainly, concentration of magnesium and calcium above 180 milligrams per liter is considered very hard. As the mineral level climbs, there are observed impacts in our homes. Bath soap combines with the minerals and forms a pasty scum that accumulates on bathtubs and sinks. The minerals also combine with soap in the laundry, and the residue doesn’t rinse well from fabric, leaving clothes dull. Hard water spots appear on everything that is washed in and around the home from dishes and silverware to the floor tiles and car (though commercial car washes use recycled water and are more environmentally friendly).
Many can live with the water spots and soap scum issues but are induced to treat their water because of the potential impacts on plumbing and appliances. When heated, calcium carbonate and magnesium carbonate are removed from the water and form a scale (lime scale) in cookware, metal hot water pipes, dishwashers and water heaters. As the scale builds up more energy is required to heat the water and hot water heater and appliances have work harder which will burn them out eventually. Thus, in hard water locations hot water heaters and other appliances have a shorter life.
The traditional treatment for hard water is a chemical softening system which is chemical process based on ion exchange can be easily tested. The water softening system consists of a mineral tank and a brine tank. The mineral tank holds small beads of resin that have a negative electrical charge. The calcium and magnesium ions stick to the beads as the hard water passes through the mineral tank. As the water is softened, the sodium (or potassium) ions are replaced and are released into the softened water. If a water sample is tested after the treatment system there is no (or very little) calcium and magnesium left in the water and the sodium or potassium is elevated. Eventually the surfaces of the beads in the mineral tank become coated with the calcium and magnesium. To clean the beads, a strong salt solution held in the brine tank is flushed through the mineral tank.
For decades magnets have been promoted and sold to eliminate water harness. Early devices involved a series of magnets, these have been replaced to a large extent in the market with alternating magnetic or electrostatic fields to adopt to the emergence of plastic piping. Magnetic water treatment has been promoted since the first half of the 20th century, yet it is still not proven that they actually work. Though many claims made by salesmen are preposterous pseudoscience, there are anecdotal stories that can not be completely dismissed. For a wonderful and funny discussion of the scientific validity of the marketing claims of the purveyors of magnetic water treatment systems see the website of retired Chemistry Professor Stephen Lower, PhD. For those of you so inclined it is witty and funny.The reason that after all this time the question of whether magnetic water treatment systems work is not definitively answered is the claim that exposing water to a magnetic field will decrease the water’s “effective” hardness. Effective hardness cannot be tested for with a chemical analysis. Magnetic water treatment system salespeople typically claim that the systems will eliminate scale deposits, lower water-heating bills, extended life of water heaters and household appliances, and more efficient use of soaps and detergents without the ongoing expense and bother of continual salt addition to a brine tank.
The effectiveness of these magnetic water treatment systems is difficult to prove or disprove. No magnesium or calcium is removed from the water by magnetic treatment, nor is it claimed to be removed. Instead, the claim is that the magnetic field decreases the tendency of the dissolved minerals to form scale through various mechanisms. Testing the water will find the mineral levels unchanged. Even though the dissolved mineral concentration indicates the water is still hard, magnetically treated water is supposed to behaves like soft water. Anecdotal stories and people's perceptions of relative softness are used to “prove” the effectiveness of the products, and the anecdotal stories cannot be entirely dismissed.
There is apparently no consensus among magnet vendors regarding the mechanisms by which magnetic water treatment occurs. As Dr. Lower points out lots of pseudoscience is thrown around, but there is no valid explanation for a mechanism of how magnetic water treatment can work. Claims by salespeople of magnetic treatment devices to be "softening the water" are simply lies. If the systems work at all and no controlled research has demonstrated that they do work, they do so by some unknown mechanism and somehow reduce the tendency of water to form and maintain lime scale. The "hardness" of water is defined by the measured amount of minerals it contains, magnetic water treatment does not claim to reduce this. Instead their claims are to reduce deposits of lime scale on pipes and appliances. Unfortunately for testing purposes, the development of hard lime scale is a slow process, requiring many years to become measurable and a serious problem.
Mike R. Powell, P.E., author of an exhaustive discussion of the research relating to magnetic water treatment entitled “Magnetic Water and Fuel Treatment: Myth, Magic, or Mainstream Science?” states “Much of the available laboratory test data imply that magnetic water treatment devices are largely ineffective, yet reports of positive results in industrial settings persist ….” “Consumer Reports magazine tested a … magnetic water treatment device…. Two electric water heaters were installed in the home of one of the Consumer Reports staffers. The hard water (200 ppm) entering one of the heaters was first passed through the magnetic treatment device. The second water heater received untreated water. The water heaters were cut open after more than two years and after more than 10,000 gallons of water were heated by each heater. The tanks were found to contain the same quantity and texture of scale. Consumer Reports concluded that the … unit was ineffective.” I called Consumer Reports to obtain a copy of the article and permission to cite it.. The full 280 word article can be found in the February 1996 volume of Consumer Reports on page 8. It appears that bottom line is, don’t waste your money on magnetic water treatment.