Comment by LinuxBender

About 20 feet in front of it. The gasses get pulled into the fan along with the mosquitoes. It works without carbonated drinks too, just slower. And that only helps if there is a swarm of them i.e. near a standing body of water. In standing water you can also use "mosquito donuts" that release a bacterium which is toxic to all species of mosquito larvae. A common brand is called "Mosquito Dunks"