Specifically designed to fit inside the Fluval® Nano Filter, the Fluval® Fine Foam Pad traps small sediments and debris for effective mechanical filtration, the crucial first stage in the filtration process. Custom-sized, it fits perfectly inside the filter chamber to prevent debris bypass. The foam pad has a pore size that allows efficient water flow, less clogging and long-lasting filtration. It is suitable for freshwater environments. Package contains 2 Fine Foams.