Aquascape 80003 Low Density Mat Pond Filtration Media Filter provides efficient mechanical and biological filtration for your pond Measures 24-inches by 39-inches and can be easily cut to your desired size and shape using a serrated knife 1.5-Inches thick and extremely easy to maintain, Only needing to be cleaned periodically For Best results we recommend combining different densities to maximizing mechanical and biological filtration Aquascape is passionate about ponds and water gardening, providing unique products, Designs, and features that stand above the competition