If you are looking for good water quality for showering, you may be considering a shower water filter. The problem with such water filters is they don't really create the clean water you are seeking for your showering, and they contribute to land fill problems and waste natural resources.
A shower water filter is increasingly popular, but for all the wrong reasons. People want shower water to smell pleasant, "not like chlorine", and to be softened to produce lots more soap lather. Some people have irrational fears of esoteric contaminants such as radon, a radioactive gas almost never found in municipal water supplies.
Even if such contaminants are present, they would have to be ingested regularly in amounts that are never consumed while showering. Heavy metals such as lead and mercury cannot be removed by relatively small shower water filters operating at typical high flow rates.
Chlorine does not damage human skin in the concentrations found in treated water supplies. If it did, swimmers -- who spend much more time in chlorinated water than shower users - would have very noticeable skin problems. It does not take mounds of bubbles to clean skin thoroughly. Shower water filters, for the most part, are irrelevant to human health.
That said, let's look at some of the technologies used in shower water filters.
Chlorine exists in shower water in two forms: "free" chlorine ions and chlorine combined with other elements such as calcium. Most shower filters use a two-stage filtration system to remove both forms of chlorine. Virtually all shower filters remove free chlorine ions with KDF -- Kinetic Degradation Fluxion. Combined chlorine is often removed with a second-stage GAC (Granulated Activated Charcoal) filter.
"Black water" often flows from shower water filters that use GAC when the filter is first installed. The black color is caused by charcoal dust, which can stain shower stall walls and tub surfaces if it is not cleaned immediately. When the dust is washed out of the filter, clear water flows.
Other substances may replace KDF and/or GAC, but they all serve the same purposes of removing free and combined chlorine. Crystalline quartz, ascorbic acid (Vitamin C), Chlorgon (calcium sulfite bound by ceramic beads), and high-tech materials such as FI (Far Infrared) ceramics may be found in shower water filters. These esoteric materials may remove 0.5 to 1.0 percent more chlorine than standard KDF and GAC filters, but cost significantly more.
The effectiveness of shower water filters depends upon the quality of raw water and its temperature. Shower water filters are necessarily small, so they can be overwhelmed by especially "dirty" water. Hot water carries more minerals than cold water, making the filter work harder.
Shower water filters must be replaced every three months or so, depending on raw water quality, water temperature, frequency and duration of showers. Ironically, spent water filters contributed more pollutants to landfills than they remove from shower water!
Some "researchers" theorize that the byproducts of KDF dechlorination - hydrogen peroxide and hydroxyl radicals - may be linked to oxidative damage to human DNA. Common sense suggests that a ten-minute daily shower in water containing such byproducts poses no significant threat to human health.
A shower water filter is a poor investment, and with its frequent disposal it burdens the environment at large. If you want to avoid taking shower water contaminants into your body, just keep your mouth shut while showering.
