What's happening biologically
When you spray a visible ant trail with a typical hardware-store product, you kill the foragers — maybe 5–10% of the colony. The colony is mostly underground or hidden inside a wall void, and it contains:
- 1 or more queens, each laying 100–800 eggs per day
- Thousands of workers + brood you never see
- Pheromone trails that get re-established within hours
Killing the visible 5% accomplishes nothing.
The fix: non-repellent baits
Professional pest control uses non-repellent products — meaning the ants don't know they've contacted them. Workers feed on a bait gel (Advion, Optigard, Maxforce Quantum) or walk through a non-repellent residual (Termidor SC, Taurus SC) and carry the active ingredient back to the colony. Workers groom each other → the active ingredient spreads → the queen eventually dies.
This is also why spraying near baits is counterproductive — the repellent spray drives workers away from the bait. Pros never do this.
Different ants need different baits
- Argentine, odorous house, pavement ants: sweet-feeding baits (Advion Sweet, Optigard)
- Pharaoh ants: highly specialized — only fipronil baits work, never spray (they bud and multiply colonies)
- Carpenter ants: combination of bait + injection into nesting wood. Often 2–3 visits.
If you've sprayed ants 3+ times and they keep coming back, you have a colony, not a few stragglers. Get a free inspection — we identify the species first, then deploy the right bait.