Seachem PhosGuardPhosGuard rapidly removes phosphate and silicate from marine and freshwater aquaria. It is not recommended for phosphate buffered freshwater. It is highly porous for high capacity and bead shaped for optimum water flow. It is spherical. Its shape allows for maximum water flow through the media. Granular phosphate removers can become compacted, dramatically limiting their capacity to remove phosphate. If the media cant come into contact with the water,