2 Pack Birdbath Protector is formulated for outdoor birdbaths that contain approximately two gallons of water or less. Keeps water clean and clear naturally through enzymes that prevent stains, organic contaminants, and mineral deposits. Our product is safe for all surfaces, wildlife, and pets that may drink from the birdbath. Our product contains non-toxic, bacteria free enzymes. Our natural enzymes safely break down organic contaminants. They are food-grade, non-toxic, biodegradable, bacteria free, and 100% environmentally friendly. 2 Pack. Usage: One cap-full weekly.