Tetra Pond Crystal Clear rapidly clears dirty pond water. It is harmless to the pond environment and binds suspended particles so they can easily be filtered out or manually removed. Tetra Crystal Water binds cloudiness caused by soil, clay particles, sand or unwashed gravel as well as organic particles, working within a few hours. It improves water quality enhancing the well-being of fish and plants. For dosage add 50ml for every 1000 litres of water.