Water Filter Review

Types of kitchen water filters

When used properly, water filters (which fall into two categories: point-of-use and point-of-entry) can significantly improve the taste and odor of a household's water.

Kitchen water filters fall into the point-of-use category, meaning they to filter water in a specific location only, in this case the kitchen sink. They include containers (pitchers or larger dispensers) that store water in a refrigerator, or faucet-mounted and under-sink models that are installed more permanently. Most point-of-use water filters use carbon filters to absorb impurities (especially odors). A reverse osmosis system, one type of under-sink water filter, also possesses semi-permeable membranes -- more aggressive filtering materials. Membranes can easily remove nitrates, arsenic and other contaminants, materials that carbon filters alone cannot achieve. However, reverse osmosis systems are expensive, and experts agree that they are unnecessary for nearly everyone. If you have a weakened immune system or have a water-contamination problem that goes beyond improving taste and odor, they are an option (but an expensive one).

Point-of-entry systems, on the other hand, work to filter an entire household's water supply. These products are usually installed in basements or outside. For stopping visual contaminants like dirt, sediment and rust with a fast flow rate and little clogging, experts say whole-house filters are king. However, to remove cysts (parasites) and certain other contaminants, point-of-use filters are still needed. In this report, we focus solely on point-of-use kitchen water filters.

Comparing water filter reviews

We found the most comprehensive kitchen water filter reviews at ConsumerReports.org. Editors compare 27 models on filtering effectiveness, ease of use and the taste of the resulting water. Comparisons rely on lab tests for lead and chloroform bacteria to indicate overall filtering effectiveness. Separate ratings are given for the filter's flow rate (how fast it filters) and clogging, as well as removing bad taste (editors create a solution made from cabbage to test this trait).

Water Technology magazine also publishes a 2008 study conducted by Water Science & Marketing for the Minnesota Department of Health, which tests water filters for one of the most difficult contaminants to filter out, perfluorochemicals (PFCs). These are the chemicals used to make Teflon and Gore-Tex. Eleven water filters pass the lab test and move onto a field test where they all prove adequate.

Experts recommend relying on lab tests by a company like NSF International, which certifies specific water filters, tells exactly which contaminants they reduce and by how much. All of the water filters recommended in this report are certified. An excellent review on TheGreenGuide.com also summarizes the NSF ratings for seven water filters, although some of those models are now discontinued.

Consumer publications like Good Housekeeping, New Zealand's Consumer magazine and Australia's Choice magazine have limited information on specific brands of water filters. However, both Consumer and Choice magazines offer solid insights about different types of water filters. ConsumerGuide.com also reviews several water filters on value, performance, ease of use and features. We did also find one comparison test at TheKitchn.com, a home design blog, but only two products are tested and the taste test was rather informal.

Lastly, we read quite a few owner-written reviews at retail websites like Amazon.com. Sears.com, Target.com, Walmart.com and Drugstore,com. We found very relevant information in reviews about replacement filters and water filter systems. We also consulted reviews written by the staff at AllergyBuyersClub.com, which sells water filters and other allergy products.