How do I know if my water filter is working?
Q. I have a water purifier in my fridge and one in my sink. Is there a way to verify that they’re working? A.L., Columbus, Ga.
A. It depends on what you’re using the filter for. Different contaminants have different effects on water quality; some might impart an unpleasant taste, odor, or color, while others, like certain metals or coliform bacteria, could harm your health. Different purifiers may target specific contaminants, so check your device or contact the manufacturer to see what yours are designed to remove. If you want to have your purified water checked, send a sample to a state certified lab. Also check with NSF International, a public health and safety certification group, to find out if your filtering devices were properly vetted.
See our Ratings and buying guide for water filters, including our top-rated carafe water filter, the Clear2O CWS100A, $23, our top-rated faucet-mounted water filter, the Culligan FM-15A, $15, and the top counter-top water filter, the Amway eSpring 10-0188, $940.
Keep in mind that you should keep your carafe water filter in the refrigerator. A water-filled carafe can become a breeding ground for microorganisms when left at room temperature.