The system will generally attract flies from a distance of 30-40 feet, depending on wind conditions. Baited system will last a long time. Effectiveness is not diminished with time. Bait will attract a broad range of species, including house and blowflies. Add water to the trap if the solution gets below the fill line.
Water is needed to drown the trapped flies.
Flies like heat, light, low wind. Place traps in sunny areas. If in an enclosed area such as a barn, place traps within 6 feet of an electrical light. Flies search low for food sources. Traps are most effective when placed 24 inches or less from ground level.