Mosquito Dunks work best in standing water that cannot simply be emptied, such as rain barrels, ponds, animal troughs, water filled tree holes, and clogged gutters, with one dunk floating on every 100 square feet of surface. Every spot where water collects needs attention, not just the largest, because some mosquitoes breed in small, hidden containers that are easy to miss.

Which spots need a dunk rather than being emptied?

Water that has to stay, such as ponds, rain barrels, animal troughs, and planter reservoirs. Containers that can be tipped out, like buckets or unused plastic pools, are better emptied, since removing standing water is a permanent fix that needs no treatment at all.

Which hidden spots are easy to miss?

Water filled tree holes, clogged gutters, and planter reservoirs. All three are listed uses for the dunks, and they matter because species such as Aedes aegypti and Aedes albopictus breed in small, concealed containers.

How should a mosquito dunk sit in the water?

Floating on the surface, where it slowly releases its Bti, a bacterium that kills mosquito larvae as they feed. Where a pond or large trough needs full coverage, a pack of Mosquito Dunks supplies one floating dunk for every 100 square feet, while a piece broken off one dunk covers a birdbath or small container.

Frequently Asked Questions

Does a birdbath need a dunk, or is changing the water enough?

Either works. Changing birdbath water at most every 4 days keeps it from becoming a breeding site, and a piece of a dunk covers it between changes.

Can dunks be used in gutters?

Yes. Gutters are among their listed uses, though clearing a clogged gutter removes the standing water for good.

Does the depth of the water change placement?

No. The dunk floats and treats up to 100 square feet of surface regardless of depth.

How many dunks does a yard need?

One for each separate water feature, plus one more for every additional 100 square feet in a larger pond.