I am surrounded by irrigation ditches & corn fields. Flies & mosquitoes ahoy. Fly spray not helpful- would get bloody spots from bites & itching. I now wrap mine from head to toe in fly sheet, shoo fly leg wraps & fly mask. Sometimes swat helps on exposed legs (but a mess). We spray the area outside the perimeter of the fence with mosquito spray & that works. I don’t think feed-through helped & with your large area forget the predators.