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. more...