In nature, the concentration of phosphates in water is usually not more than 1 mg / liter, unfortunately in the aquarium can be found concentrations even 20-30 times higher. This phenomenon, dangerous for good functioning, is favored by an excessive number of fish and by the use of feed or fertilizers with a high content of phosphates. A value of phosphates PO4 high, higher than 1 mg / liter, together with a value of nitrate NO3 higher than 25 mg / liter creates the conditions for the appearance and proliferation of algae. In the aquarium, the presence of phosphates should be limited to 1 mg / liter for freshwater aquariums and 0.1 mg / liter for marine aquariums; to obtain these values it is necessary a constant maintenance of the aquarium, as partial changes of the water, the siphoning of the bottom, the control and the cleaning of the filter are the same operations that are adopted for nitrates. The value of phosphates and nitrates must be checked monthly, with appropriate tests that have the control of po4 and control no3 of haquoss. If these values are to be raised to 1 mg / liter, it is necessary to intervene using phosphorus phosphate. This resin is able to eliminate also the silicates after removing the phosphates; it does not contain aluminum, a substance usually present in this type of product. The resin also eliminates unpleasant odors caused by the dirty filter or the remaining power supply and can be used in air filters for ozonators.