How to Get Rid of Fruit Flies and Fungus Gnats in Crested Gecko Tanks

Crested geckos are the most popular pet reptiles around the world. Its cute and easy-going nature makes it a perfect pet for people that want to care for a pet and don’t want a heavy-maintenance pet. But as a crested gecko owner, you have to deal with a set of different problems specifically in your crested gecko enclosure.

It is not uncommon for any crested gecko owner to deal with fruit flies or fungus gnats at some point. They may be found in your gecko tank or have already spilled out into the home that can be very frustrating for any owner. 

They can be problematic throughout the year and they are very common in the summer season. These flies are attracted by the fruits and vegetables that are fermenting in the heat whereas fungus gnats are frustrating because they cause serious damage to both the plants in your crested gecko enclosure and house plants.

What are fruit flies?

If you see any small flies in your kitchen, they are probably fruit flies. They can also be found in your crested gecko tank and can be very problematic. These flies are attracted by the rotten fruits and vegetables found in your gecko tank. 

An adult fruit fly has red eyes and it is no more than one-eighth of an inch in length. The front body is tan in color while its back is black. These flies can lay five hundred eggs approximately. It takes a week to complete the egg to reach the adult life cycle. 

These flies lay their eggs near the surface of fermenting foods or other moist organic materials where the tiny larvae continue to feed on the fermenting mass to thrive properly. 

What are fungus gnats?

Some people misidentified fungus gnats as fruit flies that are common in crested gecko tanks coming in with the food. These gnats look mosquito-like and have a shorter life span. These small and dark flies grow to approximately one-eighth of an inch and have long legs and antennae.

The forewings of such flies show a Y shape pattern. These gnats have small larvae with a black head and they may lay two hundred eggs approximately with a seven to ten-day life cycle. These flies live throughout the year.

Fungus gnats will not bite or transmit diseases to humans but they can be very frustrating with the larvae causing serious damage to the plants found in your house and crested gecko tank. 

Are fungus gnats and fruit flies dangerous to your crested gecko?

This is one of the most important concerns for any gecko owner when they see flies in the crested gecko enclosure. These flies are not harmful to your crested gecko but they are too annoying sometimes that your gecko may get frustrated. Fruit flies are quite nutritious and are often enjoyed by baby geckos.

Why do fruit flies and fungus gnats appear in crested gecko tanks?

Fruit flies appear when you leave sweet-smelling fruits in the tank and are also attracted to rotten fruits that are present in the tank. Fungus gnats love rotting plants and flowers and they may appear in your crested gecko tank due to the soil substrate present in the tank where they can feed on root rot or decaying leaves of the plants.

How to remove fruit flies and fungus gnats?

It is not so easy to get rid of such pesky flies but you have to find the best way to get rid of them without causing damage to your crested gecko. There are several ways that you may use to get rid of such flies and gnats.

Remove uneaten food:

Try to remove the uneaten food lying around your gecko’s enclosure as soon as possible because this uneaten food attracts the fruit flies. Remove rotting fruits from the home and your gecko’s enclosure because flies are attracted to the fermenting food that you may have not noticed lying at the back of the enclosure.

Try to wash the dishes inside your gecko’s enclosure quickly because a slight hint of rotten fruits and vegetables can attract gnats and it may be getting difficult for your gecko.

Change the substrate:

If you are stressed due to the presence of fungus gnats and fruit flies in your gecko’s tank, then what you can do is change the substrate. Remember fungus gnats lay their eggs in the soil, so if you have a soil substrate in the enclosure, choose it very carefully before finalizing your decision. 

Keep in mind that both flies’ life cycles are approximate one week and any larvae in the soil can become adults in just one week. So try to change the crested gecko substrate more often to eliminate these flies and gnats.

Mist less:

Crested geckos love the humidity which should be around 50% to 60%, so do fruit flies and fungus gnats. Try and mist less when you want to get rid of these flies. Once you have eradicated them, you may start your misting cycle again.

Keep in mind to use a digital hygrometer when you mist less, because lower misting may affect the health of your crested gecko.

Use a DIY trap:

DIY trap is a do-it-yourself trap. Many gecko owners make their DIY traps which are very effective and overall safe to use. You can use fruit juice or apple cider vinegar. You have to use a small bowl with a drop of dish soap.

Cover the top of the bowl with a tight wrap, using an elastic band. Make sure that your gecko does not climb on it and break it. Using a toothpick, make some holes on the edges of the bowl. This will help to stop these flies from crawling out the holes once they have climbed in. 

Use fly traps:

To eradicate pesky flies, crested gecko-safe fly traps such as KATCHY Indoor Insect Trap can be a great solution. This is a stylishly designed fly trap that can be put in your home with confidence. To use this, you have to set it close to your gecko’s enclosure and turn off the lights to get better results.

Keep the soil dry:

While you are using a soil substrate in your gecko’s enclosure and you are relying on the moisture level in your substrate to help boost humidity levels, letting the soil dry out may reduce the risk of fungus gnats that love to lay the eggs in the moist soil. The drier conditions can stop the fly from laying the eggs.

Use Eco fly spray:

You can use insect sprays but make sure that it should be an eco-safe spray such as Eco Defense Home Pest Control Spray. This spray naturally kills pesky flies including fruit flies and fungus gnats. This fast-acting spray is made up of natural and organic nontoxic ingredients which are safe for your pet.


Seeing fruit flies and fungus gnats in your crested gecko enclosure is very common because these flies get attracted to your reptile pet’s food. They are not dangerous to your gecko, but they are very irritating or frustrating. By using some of the useful methods, you may get rid of such flies.  

In my experience, using a KATCHY Indoor Insect Trap is the most effective solution to get rid of such flies quickly and effectively.

As Editor-in-Chief at, I bring a decade's worth of experience as a reptile enthusiast and breeder. From nurturing bearded dragons to understanding the nuances of chameleons, I'm deeply passionate about sharing my journey and expertise. My mission is to empower fellow reptile lovers, providing them with valuable insights to ensure the best care for their captivating pets. Here at, we believe in transforming knowledge into shared joy for our global community of reptile owners.

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