Change your filter with just a few simple steps. Wash your hands before unwrapping the filter. Flush filter with cold water for 15 seconds. Insert filter into reservoir. Add cold tap water. Discard your first 3 pitchers of filter water, or use this water for plants. It is normal for carbon dust to appear in your first fillings. Fill up your pitcher and enjoy great tasting water. Replace the water filter every 40 gallons or 2 months. Substances reduced may not be in all users' water.