Fungus Gnats – The Small Black Flying Bugs That Are Not Fruit Flies

You can easily confuse between fungus gnats and fruit flies.


Because both fungus gnats and fruit flies are small black flying bugs that show the same flying pattern and behavior.

They even share the same infestation sources and target the same foods in your house.

But there are some differences that are easy to spot, but many people overlook.

In this guide, you’ll find out how to differentiate between fungus gnats and fruit flies based on their appearance.

You’ll also learn the failproof methods to get rid of both fungus gnats and fruit flies from your home.

Let’s get into it.

Fungus Gnats Vs. Fruit Flies

People confuse fungus gnats with fruit flies and vice versa. But they’re two different insects despite having similarities.


Fungus gnats are smaller than fruit flies.

Adult fungus gnats are 1/16th of an inch in size. A fruit fly grows up to 1/8th of an inch in size.

Fruit flies have red eyes, black bodies, and there are yellow marks on their thorax.

In contrast, fungus gnats are black with no other color on their bodies.

Fungus gnats have thin long legs. They’ve got transparent wings that rest one over the other when these flies are stationary.

Fungus gnats resemble mosquitoes. The fruit flies look like a miniature form of a common house fly, but yellow in color.


It’s the behavior of these two flies that create a lot of confusion in you.

The worst part is that they share the same food sources and breeding grounds.

However, you can use that to your advantage.

Later in the post you’ll find out how to get rid of fungus gnats that work equally well on fruit flies.

For now, let’s find out the similarities in their behavior.

Both fungus gnats and fruit flies have zigzag and erratic flying pattern.

When fungus gnats take off, it seems like they hop rather than fly.

Fermented and ripe fruits and vegetables attract both fruit flies and fungus gnats.

Both these flies feed on them.

Fruit flies and fungus gnats lay their eggs in decaying wastes in trash cans, choked drains of your kitchen and bathroom, and damp soil beds of your house plants and yard.

The more decaying wastes are there on your property, the likelier it is for your property to have an infestation of these small flying bugs.

Moist and humid environments also attract fungus gnats and fruit flies.

So, these flies can get inside appliances like dishwashers, refrigerator, and even inside coffee machines.

Fungus gnats are a bigger nuisance than fruit flies.

Fungus gnats spread faster than fruit flies. And light from the light bulbs attract them.

If fungus gnats infestation the house overshoots, they can spread in places like bedroom.

As they’re attracted to light, fungus gnats can also sneak inside the house through open windows.

It’s common when your outdoors is a breeding ground for fungus gnats.

You’ll notice fungus gnats flocking near the windows trying to make their way inside the house.

How To Control Fruit Fly And Fungus Gnat Infestation

To eliminate the fungus gnats and fruit flies in your house, you’ll need to get rid of their breeding grounds.

And control the moisture levels of your house.

Here’s how you can do it.

Get Rid Of Decaying Wastes In Your Home And Yard

Fruit flies and fungus gnats live in rotting organic debris, decaying food wastes, compost piles, leaf litter, and choked gutters.

Eliminating decaying organic material is the key to control gnats and flies.

Ensure that you don’t let wastes accumulate on your property.

If there’s a compost bin, cover it with a lid.

Both fungus gnats and fruit flies lay eggs on cat litter boxes.

So, ensure that you’re changing the litter often and not letting it go stale.

Clean The Drains

While getting rid of flies in the house, many people skip the drains.

Big mistake!

It’s because the gunk choking the drains are a fertile egg-laying grounds for fruit flies, fungus gnats, and even for roaches and drain flies.

So, clean the drains with a reliable drain cleaner.

You can also pour white vinegar mixed with warm water into the drain to unclog the drain.

The mixture cleans the drains and kills the flies’ eggs and larvae.

Clean The Kitchen Appliances

Kitchen appliances like the refrigerator, coffee makers, and dishwashers attract both fruit flies and fungus gnats.

Both flies will sneak inside these appliances to reach the stored and decaying food wastes.

So, clean them too.

Also, ensure that your dishwasher is discharging the wastewater properly.

If it doesn’t, then the dishwasher drains are choked. It becomes the breeding ground for these household flies.

The flies that sneak inside refrigerator to access the stored fruits and vegetables die.

So, you’ll notice dead flies inside your fridge. These dead bugs and flies can also make your refrigerator stink.

Control The Dampness On Your Property

Damp areas both inside and outside the house attract fungus gnats and fruit flies.

Molds form on the damp areas. Those molds are also food sources for these flies.

Water leakages increases the dampness levels. That attracts many bugs and flies.

Check for leaky pipes and faucets in the sinks of your bathroom, kitchen, laundry room, and basement.

These areas of your home are go-to places for tiny flying insects and other bugs.

Fix any leaky pipes and faucets if you find any.

Also, don’t overwater your yard and the soil beds of your potted plants.

Damp soil is an egg laying ground for fungus gnats and fruit flies.

That’s the reason fungus gnats will lay eggs on the wet potting soil of house plants too.

Ensure that there are no wet sponges and towels lying around for days inside your home.

These flies will even lay eggs on them.

Keep Bait Stations And Fly Traps

Yellow sticky traps for fungus gnats

Bait stations, traps, and insecticide sprays go a long way to eliminate flies from the house.

As both fruit flies and fungus gnats don’t bite, so using natural methods is safest to get rid of them.

However, you can use sprays on their sources to eliminate them quickly.

Keep yellow sticky traps for at least 24 hours on the soil beds, especially on the soil beds of the house plants.

The sticky traps attract the flies, and they get stuck on them.

Both fungus gnats and fruit flies lay eggs on the damp soil beds.

So, keeping sticky traps on them is a clever way to eliminate them.

You can also prepare bait stations to draw and tap these flies.

Mix some fruit juice with dish soap. Pour the mixture in a bowl.

Cover the bowl with a plastic or aluminum foil. And poke holes on the cover.

The fruity smell from the bowl attracts these flies.

When they sneak inside the bowl, through the holes, they get stuck on the liquid because of the liquid dish soap.

Keep bait stations or traps in areas like kitchen, bathroom, laundry room, and basement.

It’s because these places are damp.

And damp and moist environments always attract flies and bugs.

Scatter Diatomaceous Earth Or Boric Acid

If you’ve noticed fungus gnats or fruit flies in the house, then diatomaceous earth or boric acid is your best bet.

Scatter either one of them on the wet soil surface or in decomposing organic matter.

It’ll kill fungus gnats, fungus gnat larvae, fruit flies, and their larvae too.

Sprinkling Epsom salt on soil beds, trash bins, and damp areas will eliminate fungus gnats and fungus gnats larvae and eggs.

Both fungus gnats and fruit flies are tiny black flies in the house that cause intense nuisance.

The presence of these little black flying bugs is a sign that your property has stagnant water problem, dampness, decaying organic wastes, and choked drains.


These are all the sources of these black flies.

Fruit flies have yellowish marks on their bodies and reddish eyes. The fungus gnats don’t.

If you’re seeing these flies in the house, then it’ll be best to eliminate their sources and follow the steps laid out in this post to get rid of them.