Thursday, November 14, 2013

How to Filter Water After It Has Been Chlorinated


I recently moved into a new house that has a chlorination system already installed.  Should I continue using it? Is it an effective method of killing bacteria in my water?  And how can I remove the chlorine after chlorination, so that I don't taste and smell it in my water?


Arlene P.


This is a good question.  Chlorination can be a very effective treatment method for bacteria and odors, and a good pre-treatment for filtering iron and manganese particles.  However, chlorination can cause problems for users on septic tanks, as the chlorine will kill the bacteria in the tank and cause the system to back up.  Besides septic tank users, many people are simply turned off by the idea of bathing in and drinking chlorinated water.  Fortunately, filtering chlorine from your water is as easy as installing a carbon filter after your chlorinator.

Due to its high absorption rate, carbon can remove high levels of chlorine from water very effectively.  A low-cost, low maintenance method of filtering with carbon is to use a carbon backwash filter.  These filters will de-chlorinate the water throughout your house and save you money on expensive cartridge filters that can also cause pressure loss through your line - no cartridges means no pressure loss, no maintenance, and no money spent on replacements.  

CWS Plus Carbon Filter
For an effective and low-cost carbon filter, we recommend the CWS Plus Carbon Filter.  This filter uses coconut shell activated carbon media, which can filter many contaminants including chlorine, hydrogen peroxide, hydrogen sulfide, and other odors that may occur naturally in well water systems.  This filter also comes with an automatic backwashing valve that can meter your water usage and backwash after either a certain amount of time or gallons of water used.  Finally, this system is under excellent warranty: 5 years for the control valve and 10 years for the tank.

See the diagram below for an illustration of how a carbon filter might be installed in conjunction with a chlorination system:
Click to enlarge
For more information, refer to our chlorination guides, available for free on our website:
For any further questions, e-mail us at or contact us on Facebook.  Thanks for the letter!