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How to Get Rid of Gnats Inside and Outside the House

Posted by on 09.19.2017

Looking for ways to get rid of gnats! No worries, you are at the right place.

Gnats are often known as “nats” or “knats“. Gnats are small sized flies ranging in size from 1/8″ to 1/10″ in length. They have two wings and in terms of appearance they resemble more to a mosquito than to a fly.

As per Wikipedia, “A gnat is any of many species of tiny flying insects in the Dipterid suborder Nematocera, especially those in the families’ Mycetophilidae, Anisopodidae and Sciaridae “.

Gnats are nuisance pests because they just lay eggs, annoy people, spread diseases, and die. Gnats are weak fliers but they torment people and become quite a distraction in the workplace.

Most species of gnats are attracted to carbon-dioxide just like horseflies and this is the reason you always find them flying around your mouth and nose.

In this article, we are going to see how to get rid of gnats, but before that let’s have a look at different types of gnats.

How to Get Rid of Gnats

Types of Gnats:

As we have already told that gnat is not a single species of flying insect, hence there are multiple types of gnats:

Fungus Gnats or Winter Gnats:

Fungus gnats are also called as winter gnats. As the name suggests these types of gnats are associated with microscopic fungi. And hence they thrive in a damp environment with decaying matter where fungi can grow.

Fungus gnats are attracted towards light and this is the reason why you mostly see them flying near windows.



Fungus gnats are often found at the places where humidity levels are quite high. The most common habitat for fungus gnats are ordinary houseplants where the soil is overwatered or the water cannot drain properly.

This creates a favourable environment for the gnats to thrive and feed on the decaying matter. Other possible breeding sources may include moisture conditions created by roof leaks or any other plumbing leaks.

Lifecycle of a Fungus Gnat:

Lifecycle of a fungus gnat can be divided into four stages – egg, larva, pupa and adult. Female fungus gnats deposit their eggs on the moist soil or decaying matter. These eggs hatch into larvae in about three days.

The larvae feed on the decaying organic matter, but in some species they also feed on the plant roots. Fully developed larvae (after about 10 days) then undergo a pupae stage. This pupae stage spans approximately 3 days. After about 4 more days in pupae stage adult fungus gnats emerge.


They cause annoyance to humans.

Some species of fungus gnats in larval stages feed on plant roots, which causes diminished growth in plants.

Eye Gnats or Grass Flies or Eye flies:

Eye gnats are known with many different names like Grass Flies, Eye Files etc. But they all belong to the ‘Chloropidae’ family of flies.

Eye gnats are very small flies which are attracted to fluids secreted by the eyes, nose, and ears in both humans and animals. And because of this these files are known to transmit eye diseases and conditions such as acute conjunctivitis (pink eye).



They prefer to live in areas with loose sandy soil but can thrive in many environments.

Lifecycle of an Eye Gnat:

Life cycle of an eye gnat is also divided into four stages. It takes 3 weeks from development of an egg to emergence of an adult during the summer season.

Female eye gnats lay eggs below the surface of loose soil. These eggs are pearlescent white and approximately 0.5 mm long. Eggs hatch into larvae in about 7 – 10 days. Larvae are 3 mm in length and are whitish in color. They feed on the organic matter.

After full development larvae undergo pupae stage. The pupae are just about 2.25 mm in length and reddish brown in color. After about 7 days in pupae stage adult eye gnats emerge.


Eye Gnats are known to spread disease causing organisms like – Streptococcal skin infection bacteria, vesicular stomatitis virus (rabies virus).

As they are attracted by eye fluids and hence they transmit eye diseases like acute conjunctivitis.

Buffalo Gnats or Black Flies:

Buffalo gnats are also known as black flies. These gnats are named so because of their humpbacked appearance. They are small sized with a size of one eighth of an inch. They typically appear in late spring and early summer.

Buffalo gnats (mostly females) swarm around birds, animals, humans and bite them to fulfil their protein needs. Males mostly feed on nectar and do not bite humans. Whereas female buffalo gnats feed on blood in order to get enough protein to produce eggs.

These gnats are attracted to carbon dioxide, perspiration, and dark moving objects, this way they can identify their prey.



Buffalo gnats are mostly found near lakes or streams because they prefer to lay their eggs near clean, fast-running water. Adult gnats can fly up to 10 miles in search of blood, but mostly they don’t have to do this, as they can easily find an easy prey near the water sources.

Lifecycle of Buffalo Gnats:

Buffalo gnats have a unique lifecycle. Female buffalo gnats lay several hundred eggs in running water streams. These eggs are yellow or orange in color. The eggs develop in running water and hatching can take from 4 -30 days.

When they develop into larvae, they find a stable surface to rest on. They have suction cup like small structure, attached to their abdomen that allows them to stick to such surfaces. Larvae are brown, gray in color with a light brown head.

Larvae then feed on other smaller organisms or organic matter and in about two weeks undergo pupae stage. Pupation takes place on stones or other stable objects in the water. Pupae period is 6 – 8 days after which adult emerges. Adult floats to the surface in a bubble of air and quickly flies away. Buffalo gnats typically live for three weeks.


They bite humans and animals to draw blood from them.

The bites are painful and often cause allergic reaction, causing them to swell and itch.

They also cause river blindness.

Sand Gnats or Sand Flies:

We have a separate article on these types of gnats. You can read it here.

Do Gnats bite?

If you are facing a gnat infestation then answer to this question must be very important for you. But actually there is no easy answer for this question.

As it totally depends on the type of gnat, some gnats like Fungus Gnats and Eyes Gnats do not bite. But there are others like Buffalo gnats and Sand Gnats which can bite and their bite is very painful.

In the following section, I am going to tell you how you can identify a gnat. After which you can decide whether your home or surroundings are infested by biting or non – biting gnats.

How to Identify Different Species of Gnats:

You can use the following table to identify different types of gnats:

Features Fungus Gnat Eye Gnat Buffalo Gnat Sand Gnat

Size 2 – 5 mm in Length 1.5 – 3.5 mm in Length 2 – 5 mm in Length 1.5 – 5 mm in Length

Physical Appearance They have blackish grey bodies with long gangly legs, multi segmented antennae. They have shiny black or gray bodies and yellow to orange-brown legs. They have black or greyish bodies, shiny thorax, short legs, and clear wings without scales. Yellowish or brownish in color with hair all over their head, thorax, abdomen, and legs.

Special Features Attracted to light Attracted to eyes Humpbacked appearance Hairy wings in vertical ‘V’ shape

Biting / Non-Biting Non-Biting Non-Biting Biting Biting

Now, after identifying that which gnat has infested your surroundings, you can proceed to the next step (i.e. gnat removal).

Recommended Reading: How to get rid of flies Indoors and Outdoors

How to Get Rid of Gnats: Call Complete Pest Control at (412) 318-4547

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How to Get Rid of Gnats Inside and Outside the House