Phosphorous in the water mostly exists in the form of phosphate which is the essence of soil nutrients and animals and plants bioplasm. Phosphorous is an important nutrient for the maturation of plants. Excessive phosphorous existing in a body of water will cause mass reproduction of algae and death to other organisms. Moreover, the decay and decomposition of algae would exhaust the dissolved oxygen in the water and lead to eutrophication.Water phosphate is commonly expressed as milligrams of phosphate per liter of water (mg/L of PO43-).