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How to Kill Mosquito Larvae

How to Kill Mosquito Larvae

Mosquitoes are not just a nuisance; they are also a health hazard. They are responsible for the spread of various blood borne diseases such as the West Nile Virus, the Zika Virus, and Eastern Equine Encephalitis.

For this reason, you should always purpose to kill mosquito larvae before it can escalate into a full-on mosquito infestation. This is the most effective method of keeping the mosquito problem at bay.

Best ways to kill mosquito larvae

These are the main solutions you should focus on for mosquito control.

Get Rid of the Water

This is the easiest way to kill mosquito larvae, but it’s not always possible if you’re dealing with larger or harder-to-reach bodies of water. Mosquito larvae won’t survive outside of the water. While they won’t suffocate on land like a fish, they also won’t have any way to find food. They either starve, get eaten by a predator, or dry out.

Use Mosquito Dunks and Bti**

Mosquito Dunk is the brand name of an insecticide used to kill mosquito larvae. These little donut-looking tokens slowly release a bacterium called Bti to prevent larvae from surviving in water.

This is one of the safest and most reliable ways to deal with young mosquitoes because Bti has no adverse effects on other animals or the environment, unlike pesticides.

Use Soap

Soap is highly toxic to many animals, including mosquitoes. A small amount of dish soap (about a milliliter per gallon) in standing water will kill any larvae within a day.

For extreme mosquito issues, hardware stores also sell special soaps that contain insecticides. No matter which soap you use, never use soap in a pond or other living environment.

Use Pesticides

The general rule of thumb with pesticides is that they are very effective but shouldn’t be your first line of defense if alternatives exist, but for an extreme mosquito problem, they may be just what you need. Mosquito bombs are the usual commercial formulation for larval pesticides and contain Methoprene. Methoprene can also be bought in granule form.

Use A Larvicide

Getting rid of standing water may be the easiest solution, but it’s not always practical. Especially in a pool, water fountain, water tank,  or ornamental ponds. In those cases, one solution is to use a larvicide. These are chemicals that kill mosquito larvae, leaving your water pristine.

Note: the water will be unsuitable for human consumption. Do not use a larvicide to decontaminate a rain barrel used to collect drinking water.

Use Chlorine Bleach

Pour some bleach into the water and the mosquito larvae will be killed immediately. Do not use bleach in any water that pets or other animals are likely to drink.

How to kill mosquito larvae in a pool

Below are some easy methods to use to kill mosquito larvae in a pool;

Check this too: Polaris Pool Cleaner How-to and Troubleshooting Guide

Pool Shock

Shocking the pool means adding massive amounts of chlorine to the pool water. The process kills the mosquito eggs, which you can’t see with the naked eye. You will need to add a generous amount of chlorine to your pool.

How much chlorine to kill mosquito larvae

Use 1 ounce of chlorine for every 1000 gallons of pool water.  This will increase the PPM level of the water in the pool to 7 PPM, which will kill the mosquito eggs and any larvae left behind in the first step.

Note: Do not swim in the pool water immediately after shock chlorination.

Mosquito dunks

Mosquito dunks are small, slow-dissolving rings that get tossed into the pool. They contain BTI, a bacterium that the larvae will feed on. Little do they know, it will also kill them.

Dunks won’t affect your water chemistry and are safe for swimmers, pets, birds, and other wildlife. Most pools will only need 2 or 3 dunks, making them one of the best ways to eradicate larvae, and they’re super affordable too!

Methoprene granules

Methoprene granules are easily added to any pool, and contain a synthetic growth hormone inhibitor that stunts the development of the larvae. Using granules allows for wider distribution in the pool compared to using dunks. A single application can last up to 30 days, ensuring the larvae won’t survive past the pupa stage.

Note: the method can also be used to kill mosquito larvae in a water fountain.

How to kill mosquito larvae in a rain barrel without contaminating water

Use a product containing Bti (Bacillus thuringiensis israeliensis), commonly known as a mosquito dunk. Bti is a nontoxic bacterium that kills mosquito larvae. It’s safe for your plants, and it will not harm people, pets, amphibians, fish, or birds. You can find the product at most garden-supply stores.

How to kill mosquito larvae without harming plants

If you have mosquito larvae in pond, eliminating them can be tricking especially if you do not wish to harm the plants.  To kill the mosquito larvae without harming plants, use BTI (Bacillus thuringiensis israelensis), a bacterial insecticide.

The insecticide is available in small, ready-to-use doughnut-shaped discs that float on the top of infected areas of your pond or in granules designed to be spread around the edge.  

Note: One application usually lasts about a month, so you must add more once a month during the summer when mosquitoes are breeding.

Natural ways to control mosquito larvae

Below are some natural ways to kill mosquito larvae;

Mosquito-eating Fish

There are many types of fish that eat mosquito larvae. If the water you are treating has the space and resources to safely house fish, consider getting some. These fish are one of the best ways to keep mosquito larvae at bay because you don’t need any pesticides, they are not harmful for the environment, and you do not have to spend money on fish food.

Vegetable Oil

Add a teaspoon of vegetable oil or extra virgin olive oil to a gallon of water kills mosquito larvae fast. The thin oil top layer on the surface will smother and suffocate the larvae, killing them in the process. Add enough vegetable oil on the water that there’s a visible gloss on the entire surface.

The main advantage of using vegetable oil is that it’s non-toxic. However, you cannot use it in fish ponds as fish need their water to have contact with the air, to ensure oxygen exchange. If you use oil to treat your fish pond, your fish will die along with the mosquitoes.

Apple Cider Vinegar

Apple cider vinegar is another effective way of eliminating mosquito larvae. It needs to be added in the same fashion as cinnamon oil, at a ratio of 15% to 85% water. Less will not work.

Cinnamon Oil

Cinnamon oil is an environmentally-friendly way of killing mosquito larvae. And it doesn’t just kill the larvae; it also kills off the eggs as well.  Add a ratio of 15% cinnamon oil to 85% water. For a 100-gallon pond, use 12 ¾ gallons of cinnamon oil.

However, cinnamon oil is not a good choice for fish ponds. Research also shows that cinnamon oil acts as a repellent for adult mosquitoes.

Can salt kill mosquito larvae?

No. Researchers find no evidence that salt-water ingestion kills mosquitoes. Summary: A new study carried out by a bevy of expert mosquito researchers in 2020 states that Salt-based mosquito-control products are ineffective

Will vinegar kill mosquito larvae?

Yes, white vinegar (or apple cider vinegar) kills mosquito larvae. All you have to do is add vinegar to water so it’s at 15% vinegar and 85% water concentration.

Will bleach kill mosquito larvae?

Yes. Bleach is a very effective mosquito larvae killer though. Bleach is best used for cleaning gutters and other areas with mosquito larvae. The bleach will effectively eliminate all the mosquito larvae. Use a tablespoon of bleach in a gallon of water.

How long does it take bleach to kill mosquito larvae?

The effect will be instantaneous. But if you do not drain water and keep maintaining the area, pupae may appear again in the future.

Will hot water kill mosquito larvae?

Yes. boiling water will kill them instantly. Make sure you drain off the water to prevent re-breeding in the same spot.

Will chlorine kill mosquito larvae?

If you use pool shocking levels of chlorine will help to kill the larvae.

Can Dettol kill mosquito larvae?

No. Dettol cannot kill mosquito larvae.