Drain Flies & Phorid Flies: The Tiny Bathroom/Kitchen Flies That Keep Coming Back
If you’re seeing tiny flies in bathrooms or kitchens that return after spraying, you may be dealing with drain flies (moth flies) or phorid flies. The secret to eliminating them is finding and fixing the breeding site, usually in organic sludge inside drains, traps, or hidden leaks. Here’s the playbook we use across Worcestershire, Herefordshire, and Gloucestershire to stop them for good.
Fast ID: Drain Fly vs Phorid Fly
• Drain (moth) flies: fuzzy/‘moth‑like’ wings, rest with wings roof‑shaped; often near sinks, showers, floor drains.
• Phorid flies: hump‑backed profile; erratic running before flight; often linked to hidden leaks and organic matter.
Why They Keep Coming Back After Sprays
• Adults breed from larvae developing in slime layers—sprays kill adults but not the source.
• Hidden plumbing defects (cracked traps, redundant pipes) continuously re‑seed populations.
Our Source‑Removal Method
• Survey and dye/torch tests to trace breeding drains or leaks.
• Mechanical cleaning of traps and gulley pots; removal of organic sludge.
• Enzymatic drain treatments to break down biofilm over several days.
• Recommendations for plumbers: repair cracked traps, re‑seal wastes, or re‑fall problem runs.
• Where activity suggests drains under floors: recommend CCTV drain survey and repairs.
What You Can Do Today
• Flush little‑used drains weekly; remove and scrub strainers and overflows.
• Keep s‑traps wet; top up with water after holidays.
• Avoid bleach while we’re running enzyme programmes—it can neutralise treatments.
Commercial Washrooms & Kitchens
We provide discreet scheduling, service reports, and hygiene plans for audits. Long‑term monitoring prevents re‑occurrence.
FAQs
• Are these flies harmful?
They’re mainly a hygiene concern and nuisance. Large numbers indicate a hidden moisture or drainage problem.
• How long until they’re gone?
Adult numbers usually drop within days once breeding sites are cleaned; full elimination depends on fixing leaks or drain defects.
• Will boiling water help?
It may reduce numbers temporarily but rarely penetrates the slime layer where larvae develop.
Book a Source‑Trace & Remediation Visit
Stop the cycle of tiny flies returning. Book Malvern Pest Control to identify the breeding site and implement a lasting fix.