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How to Get Rid of Drain Flies (5 Expert Tips)

water swirling down the drain

Drain flies, also known as sewer gnats, are incredibly annoying and can easily drive you insane. While not harmful to humans, these tiny buggers can get on your nerves. And if you’re sick and tired of them buzzing all around the house, you’ve come to the right place.

Today, we’ll highlight some of the most effective ways to get rid of drain flies quickly and easily. Whether you’re dealing with a minor infestation or a full-blown one, these tips will help you take back your home from those divider

The 5 Tips to Get Rid of Drain Flies

1. Give Your Drain a Thorough Cleaning

One of the most common reasons for a drain fly infestation is gunk and grime buildup in your pipes. Over time, grime, gunk, and other deposits can accumulate in your drains. Drain flies feed on decomposing matter and sewage, while their larvae feed on bacteria inside the drain.

Failing to clean your drains regularly creates the perfect breeding ground for drain flies. Be sure to clean your drains regularly, preferably with baking soda and white vinegar. This simple solution will get rid of drain flies and their larvae and unclog any blockages in your pipes.

drain sink bubbling from combination of baking soda and liquid
Image By: Nick Alias, Shutterstock

2. Pour Piping Hot Water Down the Drain

Another effective way to get rid of drain flies is by pouring hot water down the drains. The heat from the water will help kill off any remaining drain fly larvae and eggs, effectively eliminating your infestation for good. Do this one to two times a day for about a week or so to keep the flies from returning or laying eggs in your drains.

3. Use a Vinegar Trap to Eliminate Adult Drain Flies

Drain flies can’t resist the smell of apple cider vinegar. You can use it to create a trap that will eliminate even the most stubborn adult flies. Fill a bowl or cup with apple cider vinegar and cover it with plastic wrap. Next, make a few holes on top of the plastic wrap to create an entry point for the flies.

The flies will get into the bowl through the holes but cannot escape. You can up the ante by adding a piece of fruit for extra appeal. You can also soap the base of the bowl to make it sticky and make it harder for the flies to escape. Leave the flies inside the bowl for a few days, and they’ll eventually die off.

person holding glass of vinegar while pouring baking soda down the drain
Image Credit: batjaket, Shutterstock

4. Try Using a Drain Cleaner

For severe infestations, using a drain cleaner may be your best option. A drain cleaner contains powerful chemicals that can penetrate deep into the drains, quickly eliminating any blockages and killing off any remaining adult flies. Drano Max Gel and Earthworm are good options here.

However, it’s important to use caution when using this method, as these cleaners can often be harsh and toxic to humans. Always read the instructions carefully before use, and wear protective gear if you’re worried about exposure.

5. Scrub Your Drains With a Metal Pipe Brush

If you have really stubborn drain flies, scrub your drains with a metal pipe brush. This will help dislodge any remaining debris and blockages that are causing the infestation in the first place. Plus, it will also help kill off any remaining larvae and eggs that may be hiding inside the pipes.

Do it a couple of times if necessary, but make sure the water is running while you’re scrubbing your drain. This will help flush out all of the dead flies and other debris, keeping your drains clean and clear in the process.

person using drain snake to unclog sink
Image Credit: M-Production, Shutterstock

divider 4 How to Tell Whether You Have Drain Flies

Drain flies are small and black, measuring about 3/8 of an inch in length. They have red eyes and a gray-colored abdomen. In short, they look like tiny fruit flies but with a little more bulk and less clear wings.

To tell the difference between drain flies and fruit flies, take note of the following characteristics:

  • Drain flies are usually found in damp or wet environments, such as drains, septic tanks, and moist soil, while fruit flies tend to be more common in kitchens and other areas where there is plenty of food.
  • Drain flies have relatively long legs that extend out from their bodies when they land or rest. Fruit flies typically have shorter, stubbier legs that are more tucked in.

If you suspect that you have a drain fly infestation, there are a few simple things you can do to confirm your suspicions. For example, you could try sticking duct tape on your drain opening with the sticky side down. After a couple of days, remove the duct tape and check for any drain flies.

The flies will get stuck in the duct tape when they try to emerge. It’s best to leave the tape overnight when drain flies are most active. That way, you can get a good representation of the number of drain flies in your drains and gauge the severity of the infestation.

a clean drain with a strainer
Image Credit: Daniel Dan, Unsplash

Where Do Drain Flies Come From? Why Are They So Many?

Drain flies are often associated with unclean drains and other areas where there is a lot of moisture or standing water. They thrive in environments that are warm, wet, and dark, making drains and septic systems ideal breeding grounds for these pests.

A drain fly will lay between 30 and 100 eggs in sewage, sludge, and other types of waste, providing the larvae with plenty of nutrients to feed on as they develop. As a result, drain flies tend to be more common in older homes or buildings where there is less modern plumbing and filtration.

One of the best ways to prevent drain flies from multiplying and causing an infestation is to maintain clean drains, regularly pour boiling water down your drains, and make sure that you are not letting excess moisture or standing water accumulate anywhere in your home.

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Final Thoughts

Drain flies can be annoying and frustrating to deal with, but that doesn’t mean you should tolerate them. By using these simple tips and tricks, you can keep your drains clean, clear, and free of these pesky little critters.

Remember, the key is to get rid of any excess moisture and blockages that may be present in your home’s drains, pipes, or septic system. Failing to do so is akin to inviting a swarm of drain flies to share your home with you.

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Featured Image Credit: Semevent, Pixabay


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