Lifeguard is a broad-spectrum, non-antibiotic agent that treats the clinical signs of disease at their earliest stages in freshwater fish. Added to your aquarium, the powerful oxidizing action of HaloShield attacks and destroys disease-causing microorganisms. You don't have to be a fish expert to use Lifeguard. With this all-in-one treatment, there's no need for time-consuming guesswork. Each pre-measured dose treats infectious ailments such as fungus, ick, red streaks, milky or shredded slime, flukes, bacterial gill disease, mouth and fin rot, clamped or torn fins, and ulcers. May also be used as a preventative when adding new fish to an established aquarium. Note: This product is not suitable for scaleless fish, invertebrates, or newly established aquariums. For freshwater use only. Use as directed. Treats up to 12 gallon aquarium.