NT Labs Koi Care Potassium Permanganate is an effective powered treatment with a powerful anti parasite formulation. Koi Care Potassium Permanganate can be used as a whole pond treatment to treat parasitic infections including Costia, Trichodina and Chilodonella. Alternatively NT Labs Potassium can be used as a dip treatment in a separate volume of water to treat fish lice, leeches and for cleaning ulcers. When Do I Use NT Labs Koi Care Potassium Permanganate? Use when fish have visible external parasites such as lice and leeches, or show signs of parasitic infection (such as flicking, rubbing or gasping) or ulcers. How To Use NT Labs NT Labs Koi Care Potassium Permanganate? Potassium permanganate can be used as a dip treatment or can be added directly to the pond as a whole pond treatment. Always follow the instructions on the label for proper use.