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5 Steps To Get Rid of Gnats in Drains

Some infestations are a little challenging to deal with, but gnats — despite their frustrating tendency to fly in your face and around your food — are relatively simple to handle. If you’ve discovered gnats in your drains, it’s crucial to take action right away. Clean the immediate area, remove any old food, and then, use a chemical or natural gnat-removing solution to flush your drains.

Here are 5 steps to get rid of gnats in drains:

  1. Use boiling water.
  2. Unclog and clean the drains.
  3. Clean the P-trap.
  4. Use a pipe brush.
  5. Use an enzyme cleaner.

In this article, we’ll explain each technique to get rid of drain gnats, as well as natural methods and chemical solutions. In addition, we’ll discuss other related information regarding gnats to help you learn everything that you need to know to resolve this frustrating issue. Read on to learn more.

How To Get Rid of Drain Gnats Step-by-Step

Using the following steps, you’ll be able to get rid of any live gnats in the drain, and take out their eggs to prevent a future infestation.

1. Use Boiling Water

Boiling water will kill the majority of the gnats that have made a home in your drains. Bring a pot of water to a boil and then — very carefully — pour it down the drain. This method is unlikely to kill the eggs of gnats, but it will kill most of the live gnats, and make the additional steps much more manageable.

2. Unclog and Clean the Drains

A drain snake is a firm but flexible tool used to effectively unclog drains. The device contains a long, coiled metal wire and either a hand crank (on manual versions) or a motor. You slide the coiled metal wire down into the drain and push it down. Once it’s where you need it to be, you begin cranking, so that the coil moves around, dislodging any clogs.

There’s a lot of debris that collects and decomposes in drains. This is what attracts gnats, and therefore it’s crucial to remove it all. Use a drain snake to dislodge any debris or stuck food. After that, pour more boiling water down the drain to wash away any pieces loosened by the drain snake.

3. Clean the P-trap

The P-trap is the P-shaped pipe located beneath your sink. (There are actually several different types of drain traps as shown in the illustration below but we’ll just call it a P-trap here to keep things simple).

This pipe is designed this way to keep bad smells from coming up through the drainage system and into your sink. Unfortunately, because of it’s design, food and other debris may become trapped at the bottom.

Different types of sink drain traps compared.

Any trapped food or decomposing organic material attracts drain gnats so it’s vital to clean this area at least once a year, and especially when you’re dealing with a gnat infestation. Open up the P-trap and clean it using a brush, hot water, and mild dish detergent.

4. Use a Pipe Brush 

As we mentioned in step one, boiling water alone may kill off the majority of gnats, but the eggs may remain intact. Gnat eggs are capable of withstanding water at high temperatures, so you’ll need to take a different approach to get rid of the eggs.

One of the best ways to do this is by using a pipe brush. It does a more complete job of cleaning the drain than by using a drain snake alone. Think of a drain snake as getting the bulk of the work done and a pipe brush doing more detailed work to clean the entire drain thoroughly, including removing any gnat eggs.

5. Use an Enzyme Cleaner

Enzyme cleaners are extremely effective at cleaning drain pipes. In addition, they cover the pipes better than boiling water alone, and leave behind a layer of gel or other highly effective chemicals. The coating ensures the smooth passage of particles and grime in the future, while allowing the chemicals to remain in the drain, thus deterring any gnats (source).

Natural Ways To Get Rid of Gnats in Your Drain

In some instances, you can quickly get rid of the gnats by just flushing out your drains, which will terminate both the larvae and the urge for the gnats to return. However, if you’re dealing with a major infestation, the following methods can help you prevent as well as manage the problem.

Mix Baking Soda, Vinegar, and Salt

Baking soda is a household item often used to clean many things. This mixture is a go-to, and all the ingredients can easily be found or are already in your pantry.

Simply combine ½ cup baking soda, ½ cup salt, and 1 cup vinegar. Pour the solution down the drain and allow it to sit overnight. Do not run water during this time.

This method is better than using boiling water alone, as baking soda expands with vinegar, ensuring that it reaches every nook and corner.

After letting the mixture sit overnight, flush out the pipe using boiling water to take out all the residue and get rid of any gnats or eggs that are left behind.

Mix Soap, Water, Sugar, and Vinegar

Soap, water, sugar, and vinegar are all you need to trap and kill any gnats nearby. The water dilutes the vinegar and dissolves the sugar, creating a bitter-smelling, sweet liquid that gnats love. The soap reduces the surface tension of the solution, preventing gnats from escaping.

Simply combine a cup of water with two tablespoons of apple cider vinegar, one teaspoon of sugar, and a few drops of dish soap. Stir it well and place the container next to the drain for a few days.

After a few days, you’ll see several gnat carcasses left inside. Empty the container and refill with a fresh solution to capture even more gnats.

Combine Apple Cider Vinegar and Plastic Wrap

Baking soda is one of the most versatile items in your pantry, but apple cider vinegar is a close second. This liquid provides you with many at-home cleaning solutions, including creating a DIY gnat trap — especially if you don’t have any sugar on hand.

Just pour ¼ cup of apple cider vinegar into a mug, bowl, or jar. Cover it tightly with plastic wrap, sealing it with a rubber band. Poke holes into the plastic wrap. These holes allow gnats to enter the container, but they’re unable to escape.

Dump and replace the apple cider vinegar every two days.

Drain and Use Duct Tape

If you want to try something a little different (yet effective), try your hand at using duct tape to get rid of gnats. It can help remove some of the live flies, but it won’t do much for the eggs — so make sure to use another method in this article to get rid of the infestation for good.

Before using this method, you’ll want to ensure that the sink is clean and dry. Then, apply a strip of tape over your drain to seal it off. Leave it this way for several nights in a row — you’ll be unable to run water in your sink during this time, so keep that in mind.

The gnats will attempt to leave the drain, but the duct tape will stop and trap them.

How To Get Rid of Gnats With Chemicals

If you don’t feel like the natural methods will work for you, several effective chemical solutions are available. Cleaning products and clearing drains can eliminate the gnats since they live in or around the drain. 

When you decide to go for chemical cleaners, it’s essential to ensure you’ve read all the instructions. Don’t mix the chemicals with other chemicals or natural cleaning products. 

The following chemical cleaners will be effective in terminating the gnats in your drains.

Traditional Drain Cleaner 

A traditional drain cleaner is simple to use and makes it super easy to clean out any residue that’s left behind. Before using a traditional drain cleaner, however, ensure that the products are safe to use regularly on the pipes. Also, if you’re cleaning an area other than the bathroom, make sure that you can safely use the product.

Chemical Sprays and Repellents

Typically, most pest control killers for gnats or fruit gnats work well with getting rid of any stuck in your drains. Most of them contain caustic chemicals; hence you should check if you’re supposed to keep them out of the kitchen area. Be cautious about damage to your drains.

These chemical products (all available on Amazon.com) are excellent choices when getting rid of gnats from drains:

  • Green Gobbler Fruit Fly Goodbye Gel Drain Treatment. This gel product is specially formulated to quickly and easily kill a wide variety of small flying insects. It is safe to use since it is non-corrosive and non-caustic, so it will not cause any corrosion or rust in drains, pipes, garbage disposals, or septic systems. This product is made from Citronella, which is an all natural ingredient that is specifically formulated to kill flies and related bugs.
  • InVade Bio Drain Solution. This product is designed specifically for use in drains. This solution uses micros and citrus oil to trap and kill gnats and other small insects, as well as breaks down bacteria, scum, and any organic matter that is found in drains.
  • Fruit Fly and Drain Fly Killer. This fast acting solution kills any drain infestation including gnats, fruit flies, drain flies, and more. This product is non-toxic and safe to use in drains, pipes, and is an excellent option for both residential and commercial uses.
  • Harris Fruit Fly Drain Treatment. This effective option uses natural plant oils including Citronella, Cinnamon, and Cedarwood. It’s a fantastic option that quickly kills gnats and flies with ease. The pleasant scent leaves drains smelling fresh. The formula is safe for all drains and plumbing systems and is also child and pet friendly. 

What Do Drain Gnats Look Like?

Adult gnats are very tiny winged insects. They’re typically not more than a ¼ inch (0.64 cm) long. They may be light gray, tan, dark brown, or yellowish in color. Drain gnats have six legs, two wings, and two antennae. Gnats tend to look fuzzy because they have long hairs covering their wings and body. Some may have red eyes.

How Long Can Drain Gnats Infestations Last?

Drain gnat infestations may last from 8 to 20 days, which is the average lifespan of an adult gnat. You must act promptly to eliminate the problem, as gnats reproduce quickly. Females lay up to 40 eggs at a time and they hatch only a day later, restarting the life cycle.

Immediately remove the sewage, stagnant water, and anything that smells when you notice you might have a gnats infestation. It helps with reducing the total time the infestation lasts. 

How Do You Get Drain Gnats?

Once Inside a home, they’re usually attracted to food spillage, house plants, unsealed produce, fresh flowers, and open or overflowing garbage cans. They’ll live where any food residue might collect and in sink drains.

Drain gnats enter the home through small exterior holes and cracks — so, yes, you can have a gnat infestation even when your home is properly sealed. The insects are attracted to decomposing matter, and love dark, moist drains where they’re more comfortable and have a constant food source.

Other than being a nuisance, however, they don’t pose any serious threat. However, there’s a rare possibility that these bugs might be disease carriers because they live in sewage and standing water (source). 

How To Check for Drain Gnats

The most obvious place where you’ll find gnats congregating is around drain pipes, standing water, and anywhere that food is left out. If you suspect that you might have an infestation, use the duct tape method and place it over your drains for at least a full day. 

Check the other side of the tape to see if there are any gnats present.

If you suspect that the drain gnats are near open water drains on the outside of your property, cover the drains with plastic cups overnight. Set a rock or other weight on top to stop the cup from blowing over from the wind. After a few days, check the cups. Gnats will congregate around as they try to find a way out.

Why Do Gnats Live in Drains? 

You might be wondering why the gnats only choose to live around sinks and drains, with all the places they can possibly hide.

Gnats live in drains because it is a great source of food. For gnats, sinks, garbage disposals, and drains often contain some sweet morsels of food that they’re highly attracted to. Also, they love living in dark, warm, and moist areas.  

Because small amounts of food are constantly going down the drain, gnats and other small bugs are constantly drawn to these areas. The good thing is that they aren’t hard to get rid of, using the above steps.

How To Prevent Gnats Infestations

If you notice they’re floating around piles of garbage and dirty dishes or fruit that’s almost expired, start by cleaning the mess immediately. Maintaining a clean environment in your kitchen by keeping it free of almost rotten fruits or vegetables, soda, and other sugary substances, goes a long way in keeping gnats away from your home. 

That can be a solid solution towards preventing infestations. When they come up from inside sink drains, you have to treat them differently. You mainly target the inside of your drains, but use duct tape if you aren’t entirely sure where the source is. 

Run water through your drains every day or two since they’re attracted to standing water, and that might make them come back. 

Where Do Drain Gnats Lay Their Eggs?

The gnats can lay their eggs both indoors and outdoors. They look for the most suitable spot, and once they find it, they’ll stick around until they have no more resources or you run them out. 

Drain gnats favorite spots to lay their eggs include:

  • Outdoor sinks and drains
  • Near septic tanks and sewers
  • Bathroom, kitchen, or basement sinks 
  • Around soil containing sewage or a compost pile
  • Bathtub, shower, and basement drains 


Final Thoughts

Gnats are inconvenient and annoying, but fortunately getting rid of them doesn’t take too much work. Ensure that your property and pipes are free of standing water and make sure to clean up spills or messes as they happen. 

If an infestation occurs, both the natural and chemical methods of getting rid of these insects are effective, so choose what you prefer.

Preventative measures after you’ve removed them will ensure they don’t come back easily. Nonetheless, if DIY methods fail, don’t hesitate to call a specialist for professional advice.

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