A filter assembly for filtering water from an external source, the filter assembly includes a manifold assembly being fluidly couplable at an inlet to a source of water to be filtered and having a filtered water outlet and having a helical manifold mounting means. A cartridge has a cartridge top member for mating with the manifold assembly and has a fluid inlet, the inlet being fluidly communicable with the manifold assembly inlet and further having a sealing means, the sealing means isolating an inlet flow of unfiltered water to the filter cartridge from a non-wetted manifold assembly portion and having a cartridge coupler fluid outlet, the outlet being fluidly communicable with a filter cartridge outlet and being in fluid communication with the manifold coupler outlet and further having second sealing means, the sealing means isolating an inlet flow of unfiltered water to the filter cartridge from an outlet flow of filtered water from the filter cartridge and having helical cartridge mounting means for cooperatively engaging the helical manifold mounting means.