A filter assembly includes an outer filter assembly, the outer filter assembly including an outer filter layer of pleated polyester fabric arranged in a hollow cylindrical shape and first and second end caps for retaining the ends of the outer filter layer, and an inner filter assembly including a hollow cylindrical core having a side wall with a plurality of perforations defined therein, an inner filter layer of meltblown polypropylene disposed around an outer surface of the side wall of the hollow cylindrical core, and first and second end caps. The inner filter assembly is removably received within the outer filter assembly such that the hollow cylindrical core and inner filter layer extend within the hollow cylindrical shape defined by the outer filter layer. The filter assembly is adapted to be mounted in a horizontal orientation within a filtering chamber of a spa device.