The following article was written by Stephen Kangas, a Sallal Member and a member of Sallal’s Member Advisory Committee (MAC). Stephen volunteered to summarize his knowledge and experiences with filters that remove chlorine. (Boldface added.)
Chlorine Removal Water Filters
Sallal member Stephen Kangas, Nov 2019
When a water purveyor disinfects by injecting chlorine or chloramine into the water, it affects taste, smell, skin and hair of consumers during drinking or showering. Special water filters can be used in the home to remove the chlorine or chloramine before use. Here’s some info to guide members who are interested in removing the chlorine in their water…
The filter media used is the most important component to consider in a chlorine removal filter. Lab studies have shown that KDF (Kinetic Degradation Fluxion, a special copper-zinc alloy) is most effective at chlorine removal, especially if it is mixed with granulated activated carbon (GAC). KDF also removes heavy metals (cadmium, lead, arsenic, etc.), a bonus benefit, plus it is effective at neutralizing any bacteria build-up on any GAC that it may be used with. It is slightly more expensive for replacement media/cartridges, which are widely available. Carbon filters are also effective at removing chlorine, just not nearly so KDF and therefore must be replaced more frequently, offsetting their slightly less expensive cost over time. Carbon comes in two forms: GAC, which are ground-up particles, and “block”, which is milled out of a solid block of carbon. GAC allows build-up of bacteria colonies due to the large surface area of the carbon granules; some manufacturers add silver to counteract this bacteria buildup, but silver is considered toxic to humans and therefore the manufacturer must register with the EPA when using it in potable water filters; KDF is a non-toxic substitute for this purpose in a KDF/GAC filter. Carbon block filters are slightly more expensive than GAC and also offer the benefit of filtering some bacteria and cysts down to 1 micron in size. Carbon filters made from coconut carbon have been shown to provide better performance, so look for that.
The consumer may choose to either selectively filter only their drinking water and shower heads, or filter the water for the whole house. There are initial and long-term cost tradeoffs for each of those two approaches. Let’s look first at the least expensive option for longer term use…
Installing a whole-house filter costs more up-front, but can save long-term money over multiple filters used in the home. The filter itself can be purchased for $500 for one that has filter media replaced every 3 years at about $250, or a filter that automatically backwashes the filter for $800 and extends the filter media life to 7 years, but both require the labor costs for a plumber to install, which can exceed the cost of the filter equipment depending on who you use to do that work.
Selectively filtering water for drinking and showering can cost more longer term, and there a few options available for that…
Under-sink water filters are the least expensive option for selective filtering of drinking water; they should run about $130 complete with mounting bracket, filter housing, filter cartridge, faucet, hose, and chlorine test strips, etc, and are easy enough to install where some DIY users may choose to avoid the expense of a plumber. Replacement cartridge cost and time interval varies according to manufacturer, but should run $35 every 3 years (chlorine test strips tell you when).
There are filters that screw onto compatible water faucets that you may use in your kitchen and bathrooms. These are the most expensive longer term as they do not last very long before requiring replacement, typically after just 100 gallons or about 2 months. Many of them contain silver added to the GAC used in order to prevent bacteria buildup, which is recognized by the EPA and most DOHs as toxic to humans. Some of them do not allow for filter media replacement, forcing you to buy the entire device, further increasing the cost of use. However, in addition to certain portable counter-top filters, this may be the only option for renters to use when even simple apartment or housing alterations are not permitted, or for those who travel on business. Examples of this style are made by Brita and Pur, and typically cost $20-50 each.
There are replaceable screw-on shower head filters that remove chlorine that should run about $40 for either a disposable model or $50 for one that has an easily replaceable cartridge; either should last 3 years. Look for those that use the KDF filter media for longer life.
Portable counter-top filters are another option. The better ones use the standard KDF/GAC or carbon block filters used in the under-sink models, but they incorporate a dispensing faucet and a hose with a fitting that screws onto most kitchen faucets. That fitting may have a divertor valve to redirect the water to the counter-top filter when drinking water is needed, and then returned back to normal kitchen sink faucet use (hot water, etc). This style of counter-top filter is much more cost effective compared to other filters that screw onto the faucet, and are an option for renters who cannot install an under-sink filter system; they should run about $100 and the replacement filter cartridges about $30 every couple years for KDF and $20 every year for GAC. There are other counter-top filters that are less expensive to initially buy, but use GAC, wear out more quickly, and are sealed so that you are forced to buy the entire device each time it needs replacement filter media; these can be purchased about $40 and expect to replace them every 2-3 months.
Sources for chlorine removal filters (both KDF and carbon) include PureEarth.com, Amazon.com, and WaterFilters.net (online stores).
NOTE: (1) Reverse osmosis filters are best used for filtering out hard minerals, which is not a problem in Sallal water, are expensive and not as effective at removing chlorine. (2) Counter-top “pitcher” style filters are not discussed here, as they are largely impractical and the most expensive filter for quantities of drinking water; they are only available in GAC filters, many treated with silver. (3) As has been stated by Sallal Water Association, expect Sallal water to be treated with chlorine for at least one year from now, and maybe longer; choose a filtering solution that is cost effective for you, to minimize the impact on your budget.