Summit Mosquito Dunks 2-Pack — BTI Larvicide Discs, 30-Day Slow-Release for Birdbaths & Rain Barrels

Summit 2-Pack Mosquito Dunks are ready-to-use BTI discs that kill mosquito larvae in standing water for up to 30 days, treating about 100 sq ft per dunk.

If you’re managing birdbaths, rain barrels, garden ponds or other small pools of stagnant water, these pre-measured dunks provide targeted larval control without pesticides that harm fish or pets when used as directed. Each dunk contains Bacillus thuringiensis israelensis (BTI), a naturally occurring bacteria that specifically affects mosquito larvae and remains active in water for roughly a month.

How do these dunks prevent mosquitoes from developing?

The dunks release BTI into the water where mosquito larvae feed. When larvae ingest the bacterial spores, their digestive systems are disrupted and they don’t mature into biting adults—breaking the reproductive cycle in a single step.

• Contains BTI bacteria formulated for larval ingestion
• Slow-release action keeps water treated for approximately 30 days
• Designed for small to medium stagnant water sources like tubs and buckets

Where and how should I use each dunk for best results?

Place a single dunk in any container or low-flow water feature where mosquitoes lay eggs. The product is sized to treat about 100 square feet of surface water; replace every 30 days or after heavy rainfall that dilutes the water.

• Drop a dunk directly into ponds, birdbaths, rain barrels or clogged gutters
• For larger bodies of water, use multiple dunks spaced evenly
• Do not dissolve completely—allow slow disintegration for continuous release

Are these dunks safe around pets, wildlife, and plants?

BTI is targeted to mosquito larvae and is widely used in mosquito control programs because it has minimal effect on non-target animals when applied as directed. Follow package instructions regarding fish, aquatic invertebrates, or sensitive species in your specific water feature.

• Formulated to avoid broad-spectrum toxicity when used properly
• Safe for many outdoor household settings when directions are followed
• Check specific label guidance for fish ponds or commercial applications

What comes in the 2-pack and how long will it last?

This bundle includes two premeasured Summit Mosquito Dunks so you can treat multiple containers or replace a dunk after 30 days of activity. One dunk treats about 100 sq ft of surface water, so two dunks extend coverage across several small water sources or provide back-to-back protection at a single site.

• Bundle contains 2 ready-to-use mosquito dunks
• Each dunk covers ~100 square feet of surface water
• Active for about 30 days per dunk under normal conditions

Who this is for: Homeowners, renters, and gardeners who want simple, low-maintenance protection from mosquito populations around yards, patios, and outdoor containers. It's a practical choice if you need a focused, month-long larval control solution for small standing-water sites without resorting to broad chemical sprays.