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Buggsy Master Fly & Gnat Treatment Guide

Covers House Fly, Drain Fly, Fruit Fly, Fungus Gnat, Cluster Fly, and Horse Fly. Professional products only.


Part 1: The fly rule

Every fly problem is a breeding-site problem wearing wings. Sprays kill the adults you see; the site keeps shipping replacements. Find what they're breeding in, and the problem is 90% solved:

FlyBreeding site
House flyTrash, pet waste, compost
Drain flyOrganic film inside drains & overflow pipes
Fruit flyRipe/rotting produce, recycling residue, mop heads
Fungus gnatChronically wet potting soil
Cluster flyEarthworms outside (they overwinter in your walls)
Horse flyWet pasture/pond edges — not controllable on-property

Part 2: Protocols by fly

  • Drain flies: the film IS the nest. Stiff-brush the drain, then Nibor-D foam into drains, overflow holes, and under-slab breaks it down and kills larvae. A Gentrol point source nearby stops the rebound. Tape-over-the-drain overnight confirms which drain (they stick to it).
  • Fruit flies: remove/refrigerate produce, rinse recycling, clean the drain gunk under the trash can wheels, hot-wash mop heads. Nibor-D the drains; Gentrol nearby. They collapse in days once the food is gone.
  • Fungus gnats: let houseplant soil dry to 1–2" between waterings (kills larvae), fix over-mulched wet beds outside, Nibor-D any drain breeding. Chemical control is rarely needed once watering changes.
  • House flies: sanitation (trash lids, pet waste pickup, compost distance) + Demand CS on their resting surfaces — sunny walls, eaves, trash-area surfaces, dumpster sides. Stryker for indoor knockdown.
  • Cluster flies: they're not breeding indoors — they overwintered in your walls and emerge on warm days. Fall prevention is the whole game: Demand CS on sunny south/west exterior walls in late summer, D-Fense in attic/void entry points, seal gaps. Winter emergers: Stryker or a vacuum; don't void-treat mid-winter (dead flies in walls feed carpet beetles).
  • Horse flies: honesty section — they breed in wet areas often not on your property and ignore most treatments. Demand CS on shaded resting surfaces helps some; fans, screens, and repellent on people and horses do more.

Part 3: Product list (professional grade only)

ProductRole
Nibor-D FoamDrain & breeding-site treatment
Gentrol Point SourceIGR near breeding areas
Syngenta Demand CSResting-surface residual
Stryker 54Indoor contact knockdown
D-Fense DustCluster fly void entry points

Part 4: Safety

  • Label is the law — kitchen/drain applications especially.
  • Foam drains after hours/overnight so it can work undisturbed.
  • No residual sprays on food-prep surfaces, ever.

Part 5: When Buggsy says call a pro

  • Flies persisting after true sanitation + drain treatment — sometimes the breeding site is a dead animal in a void, a broken drain line under the slab, or a grease-trap issue, and finding it is pro work.
  • Cluster flies overwhelming a house every winter (systematic exclusion job).
  • Any commercial kitchen/food-service situation — health-code territory.

Problem bigger than the guide?

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