The product consists of 50 pieces of simple and practical bio-filter balls, which have a plastic construction with a high performance cotton filling and are ideal for the oxygen supply of your water exchange and gas. Equipped with a mesh bag to store these bio balls. Easy to rinse and use, porous design, improve bacteria filtering effect, lightweight and easy to carry. The filter beads provide a large surface area for bacteria and thus achieve a very high level of efficiency for natural biological filtration. Sufficient quantity can meet your different needs. Aquarium Filter Bio Balls which are excellent for oxygenating your water and facilitating the gas exchange process. A precious aid to restore the natural quality of the water and offer the most suitable living environment for fish. Ideal for any freshwater or saltwater aquarium, or mini reef aquarium. As water flows through the interior space, the time is increased by using nitrifying bacteria to achieve the biochemical