This Bird Bath Protector is Formulated for outdoor bird baths that contain approximately two gallons of water or less. Bird Bath protector is a 4 oz bottle. The cap on the bottle will treat 1/2 to 2 gallons of water. Bird Bath Protector prevent mineral deposits, organic contaminants and stains. Keeps water clean and clear naturally. Safe for wildlife and pets that may drink from birdbath. Non-toxic.