Clout is highly effective treatment against most parasites and protozoans such as Lernia (anchor worm), Argulus (fish lice), Ick and Leeches. It is specially formulated as wide range medication and ideal for both freshwater and marine aquariums. It is also effective Trichodina, hydra, Planaria, and Hexamita. Simply put "When in doubt, Clout it out!" One tablet treats 10 gallons.