What to Look For
Though the subject of clean drinking water is a global issue, you shouldn't rush to buy a pricey reverse osmosis filtration system. If you wonder whether it's right for you, first analyze your water supply. Most public water suppliers are required by law to publish an annual consumer confidence report that details water quality and issues. Reverse osmosis (RO) can filter out a wide range of bacterium, including giardia cysts, fecal bacteria and E. Coli; it can also filter out salts and elements like strontium, copper, nickel and lead. While public water suppliers may not report pesticide presence, RO systems can filter out up to 95 percent of the pesticides. Once water quality is assessed, then consider your household needs. If water quality isn't an issue and you want a filtration system merely for taste, you might be better off investing in a cheaper pitcher- or spigot-type filtration system.
Unlike counter- or spigot-type filtration systems like PUR, reverse osmosis filtration systems take some expertise to install and may require professional installation. On top of equipment costs, you should factor that into your budget. Also, like other filtration systems, reverse osmosis systems use replacement filters which must be changed every one to three months. Consider the ease of changing them and how much replacement filters will add to the overall cost.
Where to Buy
Overall, reviews rated Pure Water Products and TGI CT-445 by Topway Global Inc. highly. Filters have four stages—a sediment filter, a granular carbon filter, a reverse osmosis membrane and a final granular carbon stage. For under-sink systems, reviewers recommended Watts reverse osmosis systems, the Enhanced Water Filter by Pure Water Products, Rioflow USR04-50, TGI WIN445 and the Puregen ERO-535. All are available through Amazon, through a number of online water purifier companies and through Watts and Pure Water manufacturer's websites. In addition, larger manufacturers like Whirlpool and Kenmore received positive reviews for their RO filtration systems. The Whirlpool reverse osmosis filtration system WHER25, installs neatly under the kitchen sink and has a three-stage filter that lasts six months, which means one less thing you have to maintain. Kenmore products can be purchased at any Sears store.
Both Whirlpool and Kenmore reverse osmosis filtration systems are mid-range in price for under-the-sink models. As of March 2010, Whirlpool's WHER25 price ranged from $150 to $190. Kenmore's Elite Premiere Reverse Osmosis System 38556 was priced from $200 at Sears. Pure Water Products were surprisingly affordable; a three-filter system was approximately $149 but the company recommended $55 for annual membrane replacement and $20 to $30 for replacement filter cartridges.