Seachem PolyGuard Treat Bacterial, Fungal, and Parasitic Diseases for Freshwater AquariumsSeachem PolyGuard is the single most effective medication to keep freshwater fish free of disease! It is an effective treatment and safeguards against all prevalent bacterial, fungal, and parasitic diseases of exotic fish. For use in freshwater or marine aquaria. Be aware that many diseases and infections share similar physical and behavioral symptoms, e. g. clamped fins, lesions, and loss of appetite. PolyGuard treats bacterial, fungal, and parasitic