We have well water for the last 30 years. In the last year or so, I have noticed my stomach would hurt after drinking water. A year ago, I bought the 30 cup size because I drink quite a lot of water per day and the shape and spigot was best for the refrigerator. I have been very satisfied. My stomach no longer bothers me after drinking a glass of water, the dispenser takes up very little room in the refrigerator