High quality water can extend the life of your filter. . . but be aware that the manufacturer does put a time limit as well. . . some bacteria can grow at the temperatures inside of a refrigerator. . . part of the life expectancy is based on that fact. The amount of water passing through can make a difference also. . . if you use a lot of water that is really clean, it keeps the filter flushed, but if it sits for a while without use. . . it gives the opportunity for bacteria to grow. . . Most of the time. . .the things that make water unsafe, are invisible. . . so find a balance.