Nano-Tech Phosphree is a polymer resin that is chemically stable and does not leak any metal ions into the water column unlike metal-based absorbents.

Granular ferric oxide or GFO, not only clouds the water when used, but also leak small black coloured particles into the main tank.
In contrast, Phosphree keeps your tank water clear and sparkling.

Rapid reduction of phosphate in the water column could stress out corals, and in the worst case scenario, may lead to Rapid Tissue Necrosis or RTN.

Phosphree is specially designed to absorb phosphate at a much slower pace compared to other metal-based absorbents, giving time for corals to acclimate to the reduction of phosphate in the water column.

250 ml (8.5 fl oz) will remove 3 ppm of phosphate from a 1000 litres (264 gallons) marine/reef aquarium