Fruit Flies, Drain Flies & Moth Flies
Identify Them, Find the Source and Clear Them Out (2026)

Which small fly is it?

Getting the fly right saves effort. Drain flies ignore fruit traps, and fruit flies are not coming from the shower drain.

A note on names: "drain fly", "moth fly", "sink fly" and "filter fly" are all used for the same family of small, hairy flies whose larvae live in wet organic film. Whatever you call them, the treatment is the same, because the larvae are in the drain, not on the wall where you see the adults resting. Fruit flies are a different family with a different diet, which is why the two need different fixes. If you are unsure, catch one on tape and look closely: a fuzzy, moth-like fly with rounded wings is a drain fly; a smooth, tan fly with red eyes is a fruit fly.

Why Malaysian homes get them

Warmth and humidity let these flies breed all year, and a full cycle from egg to adult is short, so a few flies can become a cloud within weeks. Kitchens with fruit left out, bins that are not sealed, and floor traps in wet kitchens, bathrooms and yards give them plenty of places to breed. Unused bathrooms are a favourite: a drain that is rarely flushed builds up a slimy film that drain flies love.

Find the source: the tape test

To check whether a drain is the source, cover it overnight with clear tape or cling film, sticky side down, leaving a small gap. If flies are caught on the tape in the morning, they are breeding in that drain. Repeat on each floor trap, basin, sink and overflow. For fruit flies, a small bowl of vinegar with a drop of washing-up liquid near the suspected source shows where they gather.

Getting rid of drain flies

1. Remove the grating or strainer and scrub the drain walls and the trap with a long, stiff drain brush.
2. Clean the basin overflow hole, the underside of the floor trap cover and the waste pipe as far as you can reach.
3. Use an enzyme or biological drain cleaner to break down the film you cannot reach.
4. Flush with plenty of water, then keep that drain in use or top up the water in the trap regularly.
5. Repeat for a couple of weeks, because eggs already laid will still hatch.

Pouring bleach or boiling water down the drain kills a few adults but slides past the slime, so the flies come back. Our drain smell guide explains how floor traps work and why a dry trap causes both smells and pests.

Getting rid of fruit flies

• Put ripe fruit in the fridge or a covered container, and throw out anything overripe.
• Empty and rinse bins and recycling often; use bins with tight lids.
• Wipe up spilled juice, soft drinks and beer, including under appliances and on shelves.
• Clean the sink strainer and the kitchen drain, where food scraps collect.
• Set vinegar traps to catch the remaining adults while the source dries up.

Kitchen hygiene is the fix. Our kitchen deep cleaning guide covers the hidden places where grease and food collect.

When the flies keep coming back

If you have cleaned every drain and removed every food source and the flies still appear, especially from cracks in the floor, around the base of a toilet or near a wall, the breeding site may be hidden: a broken or leaking drain under the slab, a failed toilet seal, or water collecting in a void. That is a plumbing problem, not a pest problem. A camera inspection of the drain line shows cracks and breaks; see the cost table below. Persistent damp in a floor or wall is worth investigating for its own sake.

Keeping them away

• Run water into every floor trap and basin at least once a week, including in unused bathrooms.
• Brush out kitchen and bathroom drains regularly.
• Keep fruit covered or chilled, and take rubbish out daily in hot weather.
• Fix dripping taps and leaks that keep areas wet.
• Let pot plants dry out between waterings if fungus gnats are the problem.

Kitchens, cafes and food businesses

Commercial kitchens have more drains, grease and food waste, so small flies are a constant risk and a hygiene inspection issue. The same rule applies: find and clean the breeding sites, which usually means floor drains, grease traps, under-counter areas and bin stores, then keep them on a cleaning schedule. Our grease trap guide covers one of the usual sources, and a pest control contract adds regular monitoring.

When to call for treatment

Small fly problems are often solved without chemicals once the source is found. Our pest control services guide is candid that a fly issue is often settled by a good clean-up. Call for help when you cannot find the source, when flies persist after cleaning, when you suspect a broken drain, or when the premises is a food business that needs records.

What it costs

These are the related published ranges on ClickBina guides (indicative 2026, Klang Valley):

If the tape test points to a drain that cleaning does not fix, ask for the line to be inspected before paying for repeated sprays.

How ClickBina can help

Drain and pest problems are quoted case by case. WhatsApp us your job details for a quote: which rooms have flies, what the flies look like, what the tape test showed, and whether there are damp patches or smells. We reply within the hour, the price we agree is a flat price with no hidden charges, and a site visit is RM150, waived if you go ahead.

Sources & methodology

• ClickBina drain smell guide — floor traps, dry traps and drain call-out, clearing and camera prices.
• ClickBina pest control services guide — a fly issue is often solved by a clean-up; one-off treatment price.
• ClickBina convenience store fit-out guide — site visit wording.

How we estimated prices: every RM figure on this page is quoted unchanged from the ClickBina guides named above. They are indicative Klang Valley market ranges for 2026, not fixed rates.