We bought the 8 pack of the replacement filters after using the first filter. Not only the filtered water is clean, it tastes much better. We feel safe. We have been using ZERO water for more than a year and we never had any water borne health problem. Before ZERO water we used Brita and other filters, but now we dont feel safe with anyone else. We are going to stick with ZERO water from now on. We now plan to buy the 30 cup dispenser as we have bigger family with our child