Lee's Large Bio Pin Balls are advanced filter media designed for both freshwater and saltwater wet/dry filtration systems. This media provides essential biological filtration, efficiently breaking down harmful ammonia into less toxic nitrates, thereby maintaining a healthy aquatic environment. Additionally, their unique design promotes water turbulence, significantly enhancing the critical gas-exchange process within the filter. Each Bio-Pin Ball features 150 individual drip points, creating extensive surface area for beneficial nitrifying bacteria to colonize. The ample void space between the pins optimizes gas movement, ensuring oxygen readily contacts these bacteria for efficient biological processing. These balls can be interconnected or placed randomly within your filter box, with approximately 74 balls per gallon of media. A single cubic foot of this media offers an impressive 150 square feet of biological surface area. This product is ideal for reef aquarists and freshwater enthusiasts seeking to establish or enhance robust biological filtration in their wet/dry sumps. The large 555-count pack is particularly suitable for medium to large aquarium systems, providing ample media to support a healthy nitrogen cycle. By facilitating superior gas exchange and housing a vast population of beneficial bacteria, these bio balls are an excellent choice for maintaining pristine water quality and a thriving aquatic ecosystem.