Works well. I use the test stick before I filter periodically. My water even smells like chlorine coming out of the tap - yuck. I feel better drinking it after using the filter.
I’ve never had water taste as clean as it does with my ZeroWater filter system. I use the water in my k-cup machine and it lasts 5 times as long before I have to delime it
I have spring-fed water out in the wilderness; the meter registers 131 ppm. With ZeroWater, it's registering at 75 ppm. The water does taste fresher and feels cleaner, but I wish it registered 0.