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Hey there,
Have you ever walked into your bathroom at night and seen a tiny little moth-looking thing hovering near the sink like it pays rent?
And then the next night… there are two.
And suddenly you’re doing mental math like, “Okay, if there are two adults, there are probably 700 babies living in my plumbing.”
Welcome to the oddly personal world of drain flies.
They’re also called moth flies. They look fuzzy. They fly badly. They seem harmless.
And that’s the trap.
Because the adult is basically just the smoke.
The real situation is in the drain.
Drain flies lay eggs in the gunky biofilm that builds up inside pipes—think soap scum, hair, skin cells, sludge you don’t want to emotionally picture. The larvae live in that layer like it’s a luxury condo with a free breakfast bar.
So when drain flies show up, it’s not random. It’s a tiny flashing sign that says:
“Something in here is feeding something.”
A few signs it’s drain flies (not fruit flies):
They hang out in bathrooms, laundry rooms, and near floor drains
They’re active at night
They look fuzzy, like a mini moth with zero ambition
You see them resting on walls near sinks and tubs
And here’s the part exterminators know but most homeowners don’t:
Spraying the adults is like mopping up water while the pipe is still leaking.
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Bug Wisdom
🪠 Don’t fight the symptom and ignore the source
🧼 The smallest mess you tolerate becomes a habitat
👀 If something keeps “randomly” showing up, it’s not random
Home Tip
Do the simple test: put clear tape over the drain overnight (sticky side down).
If you catch them in the morning, congrats—you found the HQ.
Then actually clean the drain like you’re evicting someone:
scrub the inside wall of the drain (yes, with a brush)
flush with boiling water (careful with PVC)
repeat for a few nights
If it keeps happening, you may have a deeper plumbing issue or buildup further down the line that needs a pro.
Body Tip
Drain flies are a “biofilm bug.” And biofilm is also a body concept, not just a plumbing one.
If you’ve been feeling foggy, inflamed, or like your system is “sticky” lately, consider this: sometimes health is less about adding more supplements… and more about removing what’s quietly building up.
Not dramatic. Just maintenance.
Same as the drains.
If your house had a dashboard light, drain flies would be the check-engine icon. Next week we’ll talk about a bug that shows up when things are too dry—not too gross, but very revealing.
—Gabi & Bea