Esschert Design Fly Deterrents

These deterrents rely on an optical illusion. When filled with water, the glass bulb acts as a lens that distorts light and creates movement, which confuses flies and discourages them from landing or congregating in the immediate area.

They are primarily designed to deter common house flies. While they may have a minor impact on other insects, they are not a comprehensive solution for mosquitoes, wasps, or other specific pests.

No, plain tap water is all you need. The effectiveness comes from the refraction of light through the water-filled glass, so there is no need for chemicals, oils, or additives.

You should refresh the water whenever it becomes cloudy or if debris collects inside. Keeping the water clear ensures the optical effect remains strong and the glass looks clean.

For the best results, hang them in areas where flies tend to gather, such as near patio dining tables, doorways, or garden seating areas. Placing them in a spot that receives some sunlight will enhance the light-refracting effect of the water.

While the glass is durable, it is best to bring them indoors during freezing temperatures to prevent the water inside from expanding and cracking the glass. They are designed for seasonal use during warmer months when fly activity is highest.