Mosquito Bits are designed to provide a 'quick kill' of large populations of mosquito larvae. They are safe, nontoxic way to control mosquitoes before they become flying, biting, disease-carrying adults. Bits release a biological mosquito larvicide at the water's surface & as they settle it is eaten by mosquito larvae and they die within 24 hours. Can be used on all types of containerized standing water sites where mosquito larvae grow, except finished & treated drinking water. Mosquito Bits will kill the larvae of ALL SPECIES of mosquitos... that's about 2,500 species for up to 14 days.