I have a bad problem with drain flys. They're in my kitchen flying around the main sink and incinerator. These are small black flys that are very weak. We can kill them easily but they keep coming and coming. I've been pouring bleach down the drain but that doesn't seem to help. I know it's related to the rain and we're on a septic system too. What can I use?
DRAIN FLYS will thrive in the drain lines by living on organic matter that builds up over time. Bleach won't help since it goes right over where they're laying eggs and nesting. Basically there is a protective slime deep in the pipes and it's here where the drain flies prosper. They can also live right in the septic tank down in the ground and from there come up eventually getting inside the home. This commonly happens following a good rain.
To stop the invasion, pour NO SURVIVORS liquid down the drain. It works by eating the slime and buildup in your pipes. This will effectively take away their prime nest site and will have an immediate impact.
Next spray some GENTROL AEROSOL down the drain too. It's a growth regulator which will effectively stop the development of drain fly larvae so they cannot reach maturity. It won't kill anything, not even the adult flys, but it works great on the young larvae and eggs. Gentrol is labeled for use down the drain and should be applied every few weeks to keep them under control.
If you follow the two procedures listed above, the problem should go away in a week or two and eventually you won't be seeing any drain flys in the kitchen. But if you want something to control the drain flys you see right now, get the PT-565 space spray. It can be applied out into the area and will easily kill any drain flys in the room. 565 can be used daily as needed.
Here are direct links to the information and products listed above:
Drain Fly Article: https://bugspray.com/drain-flies