Seachem PhosNet is a high-purity granular ferric oxide (GFO) designed to rapidly eliminate phosphates and silicates from both saltwater and freshwater aquariums. Its advanced formulation creates an unbreakable bond, permanently trapping these nuisance compounds without the risk of them leaching back into the water column. This powerful filtration media is a critical tool for maintaining pristine water quality and inhibiting the growth of undesirable algae.

Featuring a highly porous structure with an exceptional surface area, PhosNet boasts a superior binding capacity of 1.41 mg/g, outperforming many competing GFO products and even other Seachem phosphate removers like PhosGuard. A key benefit of PhosNet is its low-dust formulation, which makes it significantly cleaner and easier to handle and rinse before use. For best results, it should be placed in a high-flow area of your system, such as a media reactor or filter bag within a canister filter or sump, to maximize water contact without tumbling.

This product is ideal for reef aquarists seeking to maintain ultra-low nutrient environments essential for the health and coloration of sensitive SPS corals. It is also an excellent solution for any aquarium keeper, from beginner to expert, who is battling persistent algae issues caused by elevated phosphate and silicate levels. By efficiently reducing these key nutrients to near-zero levels, PhosNet helps create a healthier, more stable, and visually stunning aquatic environment.