BuzzSkito Mosquito & Tick Control Specialists · Published April 28, 2026
How Mosquito Dunks Work
Mosquito dunks contain dried BTI bacterial spores compressed into a slow-release tablet. When placed in water, the dunk slowly releases BTI spores into the surrounding water column. Mosquito larvae are filter feeders — they consume the spores as they feed, and the BTI proteins disrupt their digestive system. Death occurs within 24–48 hours.
Importantly, BTI is highly specific to mosquito and black fly larvae (and a few related species). It does not affect any other organism: humans, pets, fish, frogs, dragonflies, water beetles, beneficial insects, pollinators, or birds. This specificity is why BTI is the gold standard for environmentally responsible mosquito control.
Where to Use Mosquito Dunks (and Where Not To)
✓ Ideal locations
- Rain barrels — drop one dunk per 50 gallons. Replace monthly.
- Ornamental ponds — safe for goldfish, koi, and water plants.
- Neglected swimming pools — pools that have lost chlorine and accumulated rainwater.
- Drainage ditches that hold water for weeks.
- Tree holes and stump cavities that collect rainwater.
- Large bird baths (use Mosquito Bits for small ones).
- Boats covered with tarps that pool water on top.
✗ Don’t use them here
- Active chlorinated swimming pools — chlorine kills larvae anyway.
- Puddles that dry within 3–5 days — the dunk needs water to work.
- Drinking water — although BTI is technically safe, don’t intentionally treat your drinking water at home.
Mosquito Dunks vs Mosquito Bits
Same active ingredient (BTI). Different format and use cases:
| Factor | Mosquito Dunks | Mosquito Bits |
|---|---|---|
| Format | Donut-shaped tablet | Granules |
| Release speed | Slow (30 days) | Fast (minutes) |
| Best for | Long-term sources (rain barrel, pond) | Quick knockdown / small water |
| Visibility | Visible in water (some mind this) | Sinks/dissolves quickly |
| Typical price | $10–$20 per 6-pack | $15–$25 per 8 oz |
Most Canadian homeowners with mosquito issues use both — dunks in rain barrels and ponds for set-and-forget protection, bits sprinkled into bird baths or unexpected standing water as needed.
The Bigger Mosquito Strategy
Mosquito dunks solve only HALF of the mosquito problem — they kill larvae in the water you treat. They don’t affect adult mosquitoes flying in from your neighbour’s yard, the ravine behind your house, or the creek down the street.
For complete mosquito control in your GTA yard, combine three strategies:
- BTI dunks/bits in any standing water on your property ($15/season — covers larvae from your own water)
- Habitat modification — drain anything you can, mow grass short, clear leaf litter
- Professional barrier spray — BuzzSkito’s seasonal program targets the adult mosquitoes flying onto your property from off-property sources, with a residual barrier that keeps them out for 21–30 days at a time
