How To Get Rid of Fruit Flies in Drain with these 5 Simple Methods

Are pesky, fluttering bugs floating into your face every time you place a casserole dish or cup in the sink? You’re not alone, but we’re here to help. We’ll show you how to get rid of fruit flies in a drain in this guide.

After all, fruit flies are gross little bugs. They live on our decaying food and garbage, and they lay their eggs in the places we use to clean our dishes and bodies—not exactly the house guests we’d pick for ourselves. And, if you don’t know how to get rid of fruit flies in a drain, you’re probably feeling a bit overwhelmed. This guide will help.

And, it’s surprisingly easy.

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What are fruit flies?

Fruit flies are tiny flying insects that are most commonly found around rotting fruit and garbage. They’re around ⅛-inch long and have brownish-yellow bodies and red eyes. Female fruit flies can lay up to 500 eggs, allowing them to reproduce quickly.

But, here’s the thing: Those bugs coming out of your drain, while similar in size, are probably drain flies. Drain flies are small, grayish moth-like insects, roughly the same size as a fruit fly (they’re slightly smaller). However, they have rounded, hairy wings, and lack the red eyes. Females lay fewer eggs than fruit flies, but can still lay 30 to 100 eggs in ideal conditions

Luckily this guide and its methods will get rid of both from a drain.

Fruit Flies vs. Drain Flies

Insect	Size	Description	Behavior	Reproduction
Fruit Fly	Just over ⅛ inch	Brownish-yellow coloring Red eyes No hair	Feeds on decaying food like fruit, vegetables, and garbage	Lays about 500 eggs Lays eggs on the decaying food they find so larvae can hatch and feed
Drain Fly	⅛-inch or smaller	Dark gray or black in appearance Furry wings	Feeds on organic matter in the slime coating the walls of drain pipes	Lays about 30 to 100 eggs Lays eggs in the slime coating the walls of drain pipes

What causes fruit flies in a drain?

The cause of drain flies or fruit flies in a drain is the organic debris the drain pipe contains. As we clean dishes in the kitchen sink, food matter heads down the drain and collects along the walls of the drain pipe. Sludge and slime build up over time and create the perfect environment for drain flies to feed and lay their eggs. This is similar to how maggots end up infesting trash cans, as house flies lay their eggs in the garbage.

This cycle can also occur in a bathroom sink or drain. As we wash our hands and bodies, organic matter like skin cells and hair can collect in the drain. As the organic debris decays, drain flies may move in and call that drain pipe home, with an all-they-can-eat buffet of slime and sludge.

Are fruit flies in a drain dangerous?

Like other food-obsessed insects (we’re looking at you, sugar ants), drain flies and fruit flies in drains can carry bacteria and other gross things on their bodies. However, in terms of their danger to humans and pets, there is very little risk. Also, these insects don’t bite, so there isn’t a risk of getting bitten or stung.

However, if there is a drain fly or fruit fly problem brewing, a swarm may grow in just a few days. The swarm itself isn’t dangerous, but it’s gross and off-putting, and the potential for insects to land in prepared foods exists.

How To Get Rid of Fruit Flies in Your Drain

Whether it’s drain flies or fruit flies in the drain, the following methods will help get rid of the issue. Note: It might be necessary to repeat these methods a couple of times over the course of the week to truly get rid of the problem.

Boiling Water

The first step in getting rid of fruit flies is to knock down the population and kill the existing larvae as soon as possible. To do so, boil four or five cups of water in a pot on the stove and carefully pour it down the drain. For double sinks, repeat the process on the other side, as well.

Pouring boiling water down the drain will loosen up the gunk and kill many of the adult flies (and some of the fly larvae), allowing the process to move forward faster.

Homemade drain cleaner

The boiling water will kill the existing larvae and loosen things up a bit, but it won’t do anything to clean that ideal environment that fruit flies and drain flies crave. For that, you need a scouring solution. Luckily, you probably already have what it takes to make this happen at home:

• ½ cup of salt
• ½ cup of baking soda
• 1 cup of vinegar (white vinegar is best but any vinegar will do)

Mix the solution in a large pot and pour it down the drain right away (it will foam, but don’t be alarmed). Allow the solution to work for 24 hours. The salt and baking soda should scrape away at the gunk on the sides of the pipes and break it down. For double sinks, be sure to treat both sides of the sink.

Also, a similar solution (albeit without the baking soda) can be used for other household pests like stink bugs, as well.

Brush the Drain Pipes

Another heavy-duty weapon in the war on how to get rid of fruit flies in drains is the pipe brush. These rounded brushes fit into drains and allow the user to mechanically scour the pipes, removing any debris moving forward.

Carefully pour boiling water down the drain. Give the drain 30 seconds just in case a clog occurs, otherwise, you could be brushing boiling hot water. Place the tip of the brush through the drain and push it forward using the braided steel handle. Push the handle back and forth 30 times to remove the gunk. Remove the brush and clean it with a paper towel before rinsing. Follow this up with another pot of boiling water to flush any residual organic material down the drain.

Be sure to brush both sides for double sinks.

Drain Fly Instant Fix: Drain Cleaner

At RiddaBugs, we prefer the most environmentally-friendly options for bug removal. However, we also know that some of our readers have real problems they need to deal with right away. We understand, but we want to encourage the responsible use of chemicals, insecticides, and pesticides.

However, for folks who need an immediate solution, drain cleaner will often kill larvae and remove the gunk building up on the walls of the pipes. Liquid Plumr will do the trick. Simply pour it down the drain slowly. Just be careful as this chemical should not touch skin or eyes, and users should not breathe it in, either.

Fruit fly trap

If residual drain or fruit flies are annoying you after treatment, it’s important to use fruit fly traps to get to them before they can start the cycle all over again. Here are some DIY fruit fly traps that work for drain and fruit flies:

• Place a bowl on the counter near the sink and put a piece of banana in it. Cover the bowl with plastic wrap. Poke a few small holes in the plastic wrap. Fruit and drain flies will enter through the holes, get trapped, and die. 
• Place a bowl on the counter near the sink. Fill the bowl with a cup of apple cider vinegar and a tablespoon of dish soap (we recommend Dawn). As the flies touch down for a sip of apple cider, the vinegar and soap will kill them, making this one of the most effective fruit fly traps.  

You can also use sticky fruit fly traps. These are effective at luring fruit flies and holding onto them until they die, similar to how a carpet beetle trap works.

How To Prevent Fruit Flies from Infesting a Drain

A bit of drain care and maintenance is all it takes to prevent drain flies or fruit flies from coming back. Here are some tips:

1. Around once every two weeks, pour a solution of salt, baking soda, and vinegar into each side of the drain. If fruit flies return, increase the frequency.
2. Prevent as much food matter from going down the drain as possible. Scrape plates into the garbage before placing them in the sink for cleaning. 

What If Drain Flies Come Back?

If despite your best efforts, drain flies keep coming back, there may be a problem with your drain’s trap. The trap is a U-shaped device designed to hold water to prevent sewer gasses and bugs from escaping from the main drain pipes (those large ones in your basement).

In some cases, the drain system’s vent may be clogged. In other cases, the trap could be running dry from infrequent use. In either situation, it may be best to call a plumber to investigate. 

FAQs

If you still want to know more about how to get rid of fruit flies in sink, the following frequently asked questions may point you in the right direction.

What instantly kills drain flies?

There are a few options for killing drain flies instantly. Boiling water is the most environmentally safe, but pipe cleaning solutions are also an instant solution. Note that boiling water will not correct the condition in the pipes, so a baking soda, salt, and vinegar solution may be necessary. 

Will bleach kill fruit flies in drain?

Bleach may kill some of the larvae on the way down the drain, but it’s not a recommended solution. It’s highly likely that some of the larvae will survive, and since the bleach doesn’t coat the pipes or scour the gunk loose, it’s a temporary solution at best. Also, the risks involved with bleach are similar to those with chemical cleaners, which are proven to be more effective (but still not our recommended method!).

Can fruit flies lay eggs in drain?

It’s actually drain flies that lay eggs in drains. Fruit flies prefer decaying fruit, veggies, and other foods. Drain flies prefer to eat and lay their eggs in the gunk inside drain pipes.