📋 Steps
1
Determine which gnat you have
Hovering near fruit/wine/drains = fruit fly (red eyes, tan body). Walking on houseplant soil, weak flier = fungus gnat (dark body, near plants). Hovering near drains, moth-like wings = drain fly. This ID determines everything.
2
For fruit flies — remove the source
Find and remove overripe fruit. Clean wine glass residue. Apply enzyme drain cleaner to kitchen drain. Apple cider vinegar + dish soap traps capture adults. Source removal resolves 90% of fruit fly problems within 3-5 days.
3
For fungus gnats — Bti soil drench
Soak Mosquito Bits in water for 30 minutes, strain, water all affected plants with the strained water. Repeat at every watering for 4 weeks. Let soil dry more between waterings — this kills larvae and prevents new breeding.
4
For drain flies — enzyme treatment
Apply Bio-Clean or similar enzyme drain cleaner to all household drains weekly for 6-8 weeks. Drain flies live in the biofilm inside pipes — enzyme products digest this matrix. Bleach does not work.
5
Yellow sticky traps for all three
Yellow sticky cards near infested areas capture adults of all three species. Declining weekly catch rate confirms treatment is working.
💡 Tips
- The most common gnat misidentification: people call all tiny flies 'fruit flies' but treat drains when the source is houseplant soil — or water plants when the source is drain biofilm
- New houseplants often come with fungus gnats already present — inspect new plant purchases before bringing inside and quarantine if needed
- For fruit flies specifically: check behind the refrigerator for dropped fruit that's decaying — this hidden source is missed more than any other