PURE GREEN WATER FILTER Filters Pioneer Pet Ceramic & Stainless Steel Fountains 12 Pack Compatible with Pioneer Pet Ceramic Fountains, Pioneer Pet Stainless Steel Fountains, Petco Premium Ceramic Fountains Replace filter every 2 to 4 weeks 3-Layer Filtration with Granulated Carbon and Duo-Density Polyester Pads Pack of 12 filters Keep the water in your pet's Pioneer Pet fountain tasting fresh