Algexit from easy life will rid your freshwater aquarium or pond of algae such as beard algae brush algae and string or thread algae it is harmless to fish crustaceans and plants algexit is very easy to use and you will rapidly see results just add 10ml per 100 litres of water weekly over a period of four weeks this can be extended if there is still algae present or if spores continue to germinate you can also use algexit as a preventative treatment add 5ml per 100 litres of water twice