STEM Liquid Ant Baits, 8 Bait Stations
Tidy spill proof spinosad stations for indoor ants, but not for carpenter ants.
The short version
- Homes with small sweet eating ants on kitchen counters or windowsills
- People who want sealed stations that will not leak
- Anyone who prefers a spinosad bait over borax
- You have carpenter, fire, pharaoh or harvester ants
- The ants are nesting outdoors
- You want the most widely reviewed liquid ant bait
What owners like
- Sealed stations that are not meant to spill or leak
- Fast acting claim, with results promised within a day
Common complaints
- Listing titles mention carpenter ants, but the maker excludes them
- Indoor only, so outdoor nests need a different product
- Stations need replacing as the bait dries and turns white
Based on STEM's US and Canadian product pages and a Cub retail listing. No independent owner reviews of this bait could be read, so these points reflect the maker's claims and limits rather than owner experience..
Research scores
Scored from the maker's specs and what owners report. Drew's own notes and photos will refine these.
Ownership
- Apr 2026
First bought.
Drew's hands-on notes for this product are on the way. Long-term updates will be added to this timeline.
What it does
Eight pre-filled, spill proof indoor ant bait stations from STEM that use spinosad as the active ingredient.
- Sealed, spill proof stations; peel off the activation film and set them down
- Worker ants carry the bait back to feed other workers, larvae and the queen, per STEM
- For baseboards, kitchen areas, windowsills and spaces around appliances
- STEM Canada suggests up to 8 stations normally and up to 12 per 15 square metres for heavy infestations, spaced 1.5 to 3 metres apart
A tidy option for common indoor ant trails if you want sealed, spill proof stations and a spinosad bait instead of borax. The listing title mentions carpenter ants, but STEM's own US and Canadian product pages exclude carpenter, harvester, pharaoh and fire ants, so it is the wrong pick for those, and independent owner feedback is much thinner than for TERRO.
How it compares
Specs
- Active ingredient
- Spinosad, which STEM describes as derived from soil microbes
- Stations
- 8 pre-filled stations, about 0.25 fl oz each per the Cub listing
- Use
- Indoor use only, per STEM
- Ants not controlled
- Carpenter, harvester, pharaoh and fire ants, per STEM
- Timing claim
- Starts working within 10 minutes when ants are present and kills the queen and colony within 24 hours, per STEM
- Replacement
- When the bait turns white or every 3 months, per STEM Canada
- Formula
- Water based liquid
Worth knowing
- STEM says children and pets may enter areas where the stations are in use; it does not say they may touch or play with the stations.
- STEM says to place stations on horizontal surfaces out of direct sunlight.
- STEM Canada says not to contaminate water supplies or aquatic habitats.
- Read the full label on the package before use.
Questions
Does STEM liquid ant bait kill carpenter ants?
STEM's own product pages list carpenter ants as excluded, even though some listing titles mention them.
What is the active ingredient in STEM ant bait?
Spinosad, which STEM describes as derived from soil microbes.
Can STEM ant bait be used outdoors?
No. STEM labels the liquid ant bait for indoor use only.
How often should STEM ant bait stations be replaced?
STEM Canada says to replace them when the bait turns white or every 3 months.
Sources
- STEM: Liquid Ant Bait product page (US)
- STEM: Liquid Ant Bait overview (US)
- STEM Canada: Liquid Ant Baits
- Cub: STEM Liquid Ant Bait, 8 stations
Researched 2026-10-02. We bought this product; our page is built from the maker's details and what owners report across reviews and forums. We never copy Amazon customer reviews.