API® Fungus Cure powder effectively treats fungus (Saprolegnia spp. & Achlya spp.), mouth fungus (Cotton Mouth Disease), Body Slime & Eye cloud and Fin & Tail Rot infections. Quickly controls contagious fungus and secondary bacterial infections. Helps prevent the growth of fungus on fish eggs prior to hatching. For use in freshwater aquariums. Note: This medication will cause a slight discoloration of water which can be removed with activated carbon.