Whirlpool Reverse Osmosis Filtration System WHER25

Although a water filter like the Culligan Faucet Filter FM-15A (*Est. $20) can improve the quality of water supplied by a municipality, those with a private well may be facing potentially harmful contaminants that require a reverse osmosis water filter with a semipermeable membrane. Experts recommend the Whirlpool Reverse Osmosis Filtration System WHER25, which performs almost as well as more expensive systems in comparison tests. The particularly good flow rate also surpasses faucet-mounted filters. The carbon filters last for up to six months, which is significantly longer than other types of water filters, and the reverse osmosis filter lasts at least a year. Like all reverse osmosis water filters, the WHER25 must flush water over the membrane during filtering to flush away contaminants. In this case, 5 gallons of water are wasted to produce every gallon of purified water. You must have space under the sink for the storage tank, and you may need to hire a professional to install the system. If you have normal water contaminant issues, the Culligan Faucet Filter FM-15A (*Est. $20) mounts easily to an existing faucet.

The most reliable review of the Whirlpool Reverse Osmosis Filtration System WHER25 is by ConsumerReports.org, which tests this unit against eight others of its kind and reports on the results. Editors compare filtering capability, flow rate, clogging and removal of bad taste. We also found more than two dozen reviews at Lowe's.com, where this model is sold.