With the Filtermaster Big Pack Set 5 you can easily filter contaminated aquarium water, both mechanically & biologically. Due to its particularly large surface area, the foam provides optimal conditions for the useful bacteria to settle, which also helps with the filtration of the water. Water in an aquarium will always need filtering & in order to keep it crystal clear & rid it of a build-up of harmful substances, having a filtration system is always recommended. The Filtermaster Big Pack 5 ensures clean aquarium water with both mechanical & biological filtering. The filters have a large foam surface area, which helps remove large course particles from the water & at the same time provide an ideal medium for useful bacteria to grow. The bacteria help filter the water naturally & even help filter the smallest suspended particles. Filtermaster has replaced previous filters 22616260, 2616261 & 2616265 & is suitable for use with the Eheim Professionel I 2326, 2226 & 2228, Professionel II 2026, 2126, 2028 & 2128 & e Xperience 350 (2426). The shape & texture is identical to the original products, so you can continue to have finest top quality filtration results for your aquarium. The Filtermaster Big Pack Set 5 contains 4 blue filters (PPI 10) & 11 white fleece filters. Filtermaster Big Pack Set 5 at a glance: Filter medium for use with: Eheim Professionel I External Filter 2326, 2226 & 2228 Eheim Professionel II External Filter 2026, 2126, 2028 & 2128 Eheim e Xperience External Filter 350 (2426) For efficient mechanical & biological filtration of your aquarium Replaces filter medium 22616260, 2616261 & 2616265 Identical shape & texture to the original products Contains: 11 x blue filters (PPI 10) & 11 x white fleece filters An ideal culture for useful bacteria growth thanks to the large surface area The Filtermaster Big Pack Set 1 is designed for use with: Eheim e Xperience External 350 Filter