Phosguard is required for the safe and effective removal of phosphates from an aquarium. Phosphates contribute directly to algae blooms which may deplete oxygen in an aquarium. Phosphates also inhibit coral growth in reef aquaria and contribute to eutrophication in a reef aquarium. Phosguard quickly and safely absorbs phosphates with no risk of leeching them back into the aquarium water, and since it is not an ion exchange resin, does not pass anything back into the water to replace the phosphate, unlike similar ferric oxide exchange ion resins, which exchange iron for phosphate and silicate. Phosguard is clean and does not stain the water or filters when used in an aquarium. Some heat is created on first contact with water so it is recommended that Phosguard is soaked in aquarium water before use. The spherical form of Phosguard allows maximum water flow through the media, ensuring that the media does not compact and block water from being treated. Phosguard is also efficient at removing silicates from aquarium water which contribute to unsightly diatom blooms on the substrate and aquarium glass. Phosguard is an aluminium based product and recent research was conducted which found no soluble alumina in aquariums under reef conditions with pH of 8.3, even at 3 times the recommended dose. This product does not leech soluble alumina under aquarium conditions.