Drain flies breed inside plumbing that drains slowly and has bacterial buildup. To get rid of this breeding habitat, unclog your drains and use an enzyme-based drain cleaner to kill the bacteria in your plumbing. You can also use boiling water, or a mixture of vinegar, baking soda, and salt to kill larva and eggs inside your drain. You can kill adult drain flies by covering the drain with duct tape, making homemade fly traps with apple cider vinegar, or hanging fly strips in your home.
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How Do You Know if You Have Drain Flies?
Drain flies are tiny, moth-like flies that breed and congregate near sinks, drains, and other areas with residual moisture. They look similar to fruit flies. Because both species are so small, it’s often hard to tell the difference between a drain fly and a fruit fly. However, drain flies tend to prefer walking to flying. So, if you have tiny, gnat-like flies near your sink that fly short distances before landing, it’s safe to assume you have drain flies.
What Causes Drain Flies?
A slow-draining or partially clogged drain is the most common cause of drain flies. These insects lay their eggs in small amounts of residual water trapped in drains, left in mop buckets, or even the moisture from an outdoor compost heap. Anywhere that water is allowed to stand for a few days can begin to grow bacteria, which attracts drain flies.
Will Bleach Get Rid of Drain Flies
Do not pour bleach down your drain to get rid of drain flies. Not only will bleach fail to kill the drain flies and their eggs, but it can also damage your plumbing or septic tank. As a rule, never pour bleach down your drain. Instead, use our proven methods for killing drain flies.
7 Ways to Permanently Get Rid of Drain Flies
A drain fly infestation can be an extreme nuisance. The flies will congregate and breed, spreading through the areas where they’ve laid their eggs. However, there are several fast and effective ways to kill these pests for good. Here are the best methods for killing drain flies:
Check Your Drain for Blockages
Many drain fly infestations are caused by a partially blocked or slow-draining sink or shower. The water that drains slowly leaves a filmy residue on the inside of your pipes. This creates the perfect habitat for drain flies to feed on bacteria and lay eggs. In order to eliminate this problem, begin by taking these steps to unclog your sink:
- Use this drain clog remover that has been bought and tested by our editors.
- Pour a standard drain-cleaning substance—such as Drano—down the drain that is infested with flies.
- If the drain continues to drain slowly, contact a professional plumber for help unclogging your drain.
The first step to eliminating and preventing drain flies is to make sure your drains are completely clear of obstructions. This will prevent bacterial buildup in your drains. Without bacteria to feed on, drain flies will have nothing to eat. This will begin to eliminate your drain fly problem.
Use a Foaming Enzyme Drain Cleaner
The bacteria-breeding film that grows on the inside of pipes is the main food source for drain fly larva. Removing this buildup kills drain flies fast. To clear your pipes of bacterial buildup, use an enzyme drain cleaner.
- This enzyme drain cleaner removes buildup from pipes and clears clogs.
- By removing bacterial buildup, you remove the main food source for young drain flies.
- Once your pipes have been cleaned with an enzyme drain cleaner, drain flies will die from lack of food.
Using a powerful drain cleaner is a key step to make sure drain flies are dealt with permanently. Other methods can kill adult flies, but thoroughly cleaning your drain disrupts the drain fly life cycle, stopping the infestation at its source.
Vinegar, Baking Soda, and Salt
If you wish to avoid using chemicals to clean your drain, you can make your own drain cleaner from household materials. By mixing baking soda, salt, and vinegar you will have a foaming drain cleaner that kills drain flies and their larva. Here’s how to do it:
- Pour 1 cup of baking soda into the drain.
- Mix together 1 cup of white vinegar and ½-cup of salt
- Pour the salt and vinegar mixture into the drain.
- Allow the mixture to sit overnight.
This simple drain cleaner can help to clean your plumbing and get rid of drain flies. It’s a simple trick that works well in a large variety of cases.
In order to kill drain fly eggs and larvae in your plumbing, pour boiling water down the drain. This solution requires no trips to the store and can provide great results. For this method:
- Bring 8 cups of water to a boil.
- Slowly and carefully pour the boiling water down the drain.
- Repeat this process to ensure you’ve killed all drain flies.
The heat of boiling water will instantly kill drain flies and their larva. So, you may be able to control the infestation using nothing more than water.
A simple solution for killing drain flies is to place a piece of duct tape over the drain overnight. Then, remove the duct tape in the morning. If the drain is infested with flies, you will see many of the little pests stuck to the tape.
- Place a piece of duct tape over drains that you believe are infested with drain flies.
- Leave the duct tape in place overnight.
- In the morning, remove the duct tape to see dead drain flies stuck to the tape.
- This method is great for testing drains to see where drain flies are coming from.
The duct tape method is excellent for identifying the source of a drain fly problem. If you don’t know where your drain flies are coming from, put duct tape over several drains in your home overnight. The pieces of duct tape that have dead flies stuck to them indicate where your infestation problem is coming from.
Apple Cider Vinegar with Plastic Wrap
If you want to kill adult drain flies fast, you can use bowls, plastic wrap, and apple cider vinegar. Simply fill each small bowl partway with apple cider vinegar and cover the bowl with tight-fitting plastic wrap. Next, use a pen or pencil to puncture several small holes in the plastic. The flies will enter through the holes in the plastic wrap, become trapped, and drown in the vinegar.
- Fill several small bowls halfway with apple cider vinegar.
- Cover each bowl with plastic wrap.
- Use a rubber band to ensure the plastic wrap is tightly sealed in place.
- Puncture 5–7 holes in the plastic wrap with a pen or a pencil.
- Leave the bowls out in any room with adult drain flies.
- The flies will become trapped and drown in the apple cider vinegar.
Using these simple drain fly traps can quickly kill adult drain flies while you use a drain cleaner to destroy the eggs and larva. In just a few days, you can reclaim your home from these pests.
Fly Paper/Fly Strips
In order to clear adult drain flies out of a room quickly, hang fly strips or fly paper. These strips are scented to attract flies. Plus, drain flies only fly short distances before landing. Using fly strips will quickly attract and kill drain flies.
- Use these scented fly strips to attract and kill drain flies.
- Hang fly strips in rooms where drain flies are present.
- Within 2–3 days, the adult drain flies will be caught and killed.
Once you kill the obnoxious drain flies flying around your home and scour your drain with powerful cleaning solutions, you’ll once more feel at peace. Drain flies are a nuisance, but you have the ability to kill them yourself.
How to Prevent Drain Flies from Coming Back
Once you’ve killed the drain flies in your home prevent them from coming back by regularly cleaning and checking your drain for clogs. If you have frequent drain fly problems, use an enzyme-based drain cleaner every 3 months to prevent drain flies. If the drain flies have no place to breed, your home won’t be invaded.
How Long Does it Take to Get Rid of Drain Flies?
You can get rid of drain flies in your home in 2–3 days by using these strategies:
- Use a drain snake and drain cleaner to unclog drains infested with drain flies—stagnant water in a partially clogged drain creates a breeding ground for these insects.
- Destroy the bacteria drain flies feed on by using an enzyme-based drain cleaner.
- Pour a mixture of baking soda, salt, and vinegar down the drain to clear clogs and kill bacteria.
- Pour boiling water down your drain to kill drain fly eggs and larva.
- Cover drains with duct tape to identify where drain flies live and to kill flies that try to exit the drain.
- Make fly traps from bowls of apple cider vinegar covered with plastic wrap.
- Hang scented fly strips to attract and kill adult drain flies.
Whether drain flies have invaded your kitchen sink or a shower drain, these tactics will work quickly to kill drain flies at all stages of life—from egg, to larva, to adult flies.