How To Stop Bathroom Mold

What Are Drain Flies and how do we get rid of them?

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Drain flies may occur much more often than the average person realizes. Have you ever walked into a kitchen only to discover small flying insects? What are they, and where do they come from? Some people might think they are flies, gnats, or even moths.  What is the story behind these flying bugs? The flying bugs are called drain flies, and they’re a  common complaint with plumbers. Drain flies are a common pest in homes and businesses. You can commonly see them in bathrooms and kitchens, especially around slow-moving drains. 

Drain Flies Are Harmless But still A Nuisance 

Some homeowners worry they might be hazardous, and this is understandable. Although they have no idea what drain flies are, most people believe they are a sign of poor hygiene or uncleanliness. The average homeowner can eradicate them with an over-the-counter product in most cases. Much will depend on the severity of the problem. If the problem persists, you may need to contact a local exterminator for assistance.

Drain Flies Are Considered A Fly And Not A Moth

As Dipteran insects, drain flies are classified as “true flies,” which are distinguished by having just one set of wings. There are many names given to this pesky insect, such as moth flies,  sewage gnats, and even sink flies, just to name a few. For identification purposes, these flying bugs have moth-like wings. This is why drain flies are also referred to as “moth flies,” since they have a large number of thick hairs around their head and eyes.  With their grey hue and their wings, they resemble a miniature moth. However, they belong to the Psychodidae family and come in a wide range of colors, sizes, and shapes. 

They Breed In Damp Kitchen And Bathroom Drains

The most common place for them to breed is in damp regions of your home, such as your kitchen or bathroom sink that have slow-moving or clogged drains. However, its larvae can also be observed crawling over the moist borders of shower stalls and other damp bathroom locations. You’re more likely to observe drain flies at night since they’re nocturnal, but they’re drawn to light as well, so they can also be seen during daytime hours. Since they can’t fly well, drain flies spend much of their time traveling around damp surfaces in your bathroom and kitchen rather than randomly flying around.

A buildup of organic debris in a drain may attract drain flies, which are more prevalent while a blockage is forming. For example, it may thrive in a slow-moving bathtub or shower drain where the water becomes stagnant.

Drain Flies Will Not Harm Humans

Drain flies are not a threat to human health or safety. You don’t have to worry about drain flies in your kitchen, bathroom, or any other part of your house if you see them. If they can get inside your home, they and can find the right place and conditions to deposit their eggs and breed–––they will. They are opportunistic insects. However, other related flies in the same Psychodidae family feed on blood. They are called sand flies, a sub-genus of drain flies, which are less frequent in North America than drain flies. 

There Are Some Excellent Over-The-Counter Products

Many over-the-counter products will remove drain flies from your home. As a caution like any over-the-counter chemicals, read and follow the directions carefully, especially where food gets prepared. 

Prevention Is Always Better Than The Cure

Prevention is the best way to keep drain flies at bay. You can do this by keeping organic material from building up in your drains where they can lay their eggs. Locate where food, hair, and other bathroom products accumulate in the drain and remove it. Black slime is an issue in bathroom drains. The main cause is hair, phlegm, soap, and other products that accumulate in your bathroom drain, which is a big draw for drain flies.   

Once the organic debris or obstruction gets removed, it will destroy any eggs or larvae. Of course, there will still be adults buzzing about, but they only have a 20-day life span as adults, and without a location to mate or lay eggs, they’ll be unable to spread their infestation any further.

Clean Your Drains And Kill The Larva

The next step would be to kill the larva to prevent future generations of flies. You must do this by cleaning the drain. There are a couple of ways this can be done, including:

  • Cleaning the area with a brush can dislodge organic matter in the drain and make the area less attractive to future infestations. You may want to follow up by removing any remaining debris, like hair.
  • Purchase an enzyme cleaner meant to break down organic matter. InVade® Bio Drain cleaners are a popular and safe option. Closely follow instructions on the bottle. You can use this in both the shower drains and bathroom sinks. The key is using a tough, non-toxic cleaner to eliminate debris and larva that will not harm your plumbing system
  • Rid yourself of any remaining adult flies with a swatter and safe insect spray to use in your home. Follow the directions closely and keep away from food or drink.
  • A sure-fire way to keep your bathroom drain fly-free for the future is to ensure you are cleaning the drains regularly to prevent hot spots for drain fly breeding.
Brandon and Family, Licensed plumbing contractor

Family Owned & Operated

My name is Brandon Mageno. I'm the founder, President, and CEO of Big B's Plumbing Company. As the founder, I never thought about being average or good. My passion for being the best plumbing company in Southern California has always been the same. Providing plumbing services to this great county is simply in my DNA. Nothing makes me happier than to see a satisfied customer. Learn More About Us

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