Healthy Ponds 52022 Pond Water Colorant/Spray Pattern Indicator Pellets (4), Reflection (Black); Each Pellet Treats 4,100 Gallons of Water Pond water colorants are essential once water clarity has been achieved using healthy ponds products Shades pond and limits sunlight penetration, reducing weeds and algae; within 24 hours pond will take on a beautiful appearance that reflects the sky Safe for fish, plants, pets and humans; made from certified food quality dyes Simply add the correct number of pellets for your pond size; one pellet treats up to 4,100 gallons Can also be used in a spray tank at a ratio of 1 pellet per gallon of water to avoid overlap and missed areas when spraying turf, grass or gardens