Prozap LarvaGuard Mosquito Granules provide 30 day control of mosquito larva in containerized water, the ideal mosquito breeding site. The use of methoprene inhibits mosquito larva from developing into breeding, biting adults. Slow release granules sink to the bottom and provide treatment of the entire column of water, not just the surface. Ideal for use in containerized water gardens, ornamental ponds, clogged rain gutters, old tires, bird baths, livestock/horse watering troughs and other areas of standing water. Safe for livestock, pets, fish, and birds.