GO-Green fine Random Strand, Lime Green, dual sided aquarium / pond filters give you two filters in one. The first side captures the larger particles, debris, and uneaten food. The second side catches the finer particles left behind. Polyester Fiber Filter Media for pond skimmers, and filtering waterfalls and aquariums. This is a premium quality product that will withstand many wash outs, reducing waste in landfills. Aqua-Flo is an industry leader in providing well designed, quality products to make maintaining your system easier, and more cost efficient.