Product review (5 stars): GE MSWF Refrigerator Water Filter
I live in the Tucson, AZ area and our water is very hard. I test my water regularly out of the tap and it shows 240. I test the water out of my R/O system and it tests at 22. The water coming out of my ref with the GE filter which comes from the R/0 system is 20. I have the cleanest water in our neighborhood. The only issue I had was the GE filter took a couple of months to get back to "normal" testing range. When I fist installed it, the water tested at 40. Now that it's back to "normal" I'm pleased. Also the install was easy - reading the simple directions took longer that the install. You just twist off the old one and twist on the new one and then run about 5 gallons through the system.