1 Prepare for safe work
Ventilate the room, put on gloves, and first test the cleaning agent in a hidden area. Protect children, pets, textiles, and sensitive surfaces.
⚠ Warning: Never mix bleach with vinegar, acids, ammonia, or other cleaners. The mixture can release toxic gases.
2 Determine the condition and cause
Overnight, cover the suspected drain with transparent adhesive tape without closing it completely to confirm if the flies are coming from there.
3 Perform the key check
Mechanically clean the slime from the strainer, overflow, and accessible siphon with a brush, then rinse with warm water and detergent.
4 Do the repair or maintenance
Repair leaks and regularly run water into rarely used drains. Using insecticide without removing the organic film yields only short-term results.
? Tip: Photograph the initial state and change only one thing at a time. This makes it easier to determine what really solved the problem.
5 Test the result
Remove any cleaner residue according to the label, dry the surface, and inspect the result in daylight. If the problem returns quickly, find the source of moisture, dirt, or malfunction.