PhosGuard is a high capacity and high efficiency filtration product for removing phosphates and silicates from marine or fresh water aquaria. Unlike competing products, PhosGuard is bead-shaped for optimum flow characteristics and has an exceptional porosity for enhanced capacity. PhosGuard has a working capacity to remove 20 to 60 mg/L phosphate in 100 gallons with a similar impact on silicates. It may be used continuously or intermittently, and will not release removed phosphate. PhosGuard will cause a decline in hair algae and enhance coral growth.