Do Koi fish Eat Mosquito Larvae? Cool Facts!

Koi fish are ferocious eaters and will eat anything that comes into contact with the water. However, as Koi fish average about 3 feet in size, they typically have their sights set on larger prey than Mosquito Larvae. If you’d like your Koi fish to consume greater amounts of mosquito larvae, decrease their food just a little, and they should seek supplemental food like larvae and other pests out more.

Mosquito larvae can be found in still and stagnant water will will only apply to natural ponds where water movement is limited. Koi fish and other pond will will eat mosquito larvae if it were to settle on your pond. However, we hope that your pond is clean and has surface water movement which will not attract mosquitos. Smaller koi fish will happily feed on such small pickings but koi fish prefer much larger food portions.

There are other pond fish that you can enlist to feed on mosquito larvae as well. Finally, there are plenty of additional live foods that your Koi fish will love.

Why Mosquitoes Suck (Blood)

Does anyone actually like mosquitoes? You’d be hard-pressed to find someone with anything but annoyance or outright hatred for these blood-sucking creatures. Along with the maddeningly itchy bites, mosquitoes can even pass on diseases like malaria, West Nile, Rift Valley, and more.

If you have a pond or water feature in your backyard, you might find that, to your dismay, mosquitoes have made themselves right at home. These guys feel especially cozy around stagnant water. This is required for the first step in the mosquito life cycle, after all.

Mosquito Life Cycle

1. Female mosquitoes lay their eggs on the surface of -preferably stagnant- water.

2. From here, the eggs take a mere 48 hours to hatch into mosquito larvae.

3. The mosquito larvae will gradually transform into pupae, over about 5 days.

4. Finally, mosquito pupae take just 2-3 days to make their final metamorphosis into fully-fledged adult mosquitoes. The adults will promptly pair off to mate, and then the females will be off in search of blood.

As a matter of fact, only female mosquitoes suck blood. This is because they actually use blood as a prenatal supplement, as it is very hydrating and fatty, not to mention chock-full of amino acids (which create protein and are the building blocks of life).

That’s all well and good, but what if you don’t want mosquitoes around? If your pond is to blame for the swarms around your house, what can be done?

There are a few solutions, and one of the best of these is -you guessed it- fish. These swift, scaled creatures do not take much encouragement to eat bugs and other pests, thankfully! All you need are some proper mosquito-eating fish, such as:

Mosquito Larvae
Close up a group of Mosquito pupae underwater


If you’re looking for a mosquito-eater, look no further than the Guppie! This cute, colorful little fish can eat almost its own weight in mosquito larvae, every day! If you’re wondering, ‘do Koi fish eat mosquito larvae?’ well, they’re more likely to eat your guppies, actually.

The larvae are so small as to be almost unnoticeable – at least, Koi fish will really have to look. Guppies, on the other hand, are only 2.5-inches, max! They are also easy to spot because they are very colorful.

Guppies are only found in a pond in countries that have warmer climates. And, obviously, you can’t keep guppies with koi or they will become the favorite snack for your koi.


If you think the guppie is an impressive mosquito larvae hunter, you’ll be amazed by the Mosquitofish. The Mosquitofish earns its name from the hundreds of mosquito larvae that each one eats in a day. At 1.5-3 inches, Mosquitofish are also an ideal size for hunting mosquito larvae. On top of this, they eat pests like water beetles, and caddisfly and mayfly larvae, as well.

Mosquito Fish tend to reproduce quickly, however. They can quickly overpopulate your pond if they are not kept in check. This is where you will probably want a few Koi.

You may have wondering which fish are best to lower or eradicate mosquitoes when, as it turns out, Guppies and Mosquitofish will work considerably better. Koi can then be employed to keep your Guppie and Mosquitofish population under control.

There are a couple of additional things about Mosquito Fish you will want to know: they are considered invasive in the US, in WA and MA. They are recommended in legal areas only, and really only if you have a serious mosquito problem. Otherwise, another, less invasive fish variety -or two- can also do the trick.


Do Koi fish eat mosquito larvae? For these large fish -up to 3 feet in size- mosquito larvae are tiny and can be rather difficult to find. What’s more, they make barely a mouthful. Alternately, Goldfish rarely exceed a foot in size in residential ponds, making it much easier for them to find and fill their bellies on the larvae.

If you use Goldfish to get rid of mosquito larvae in your pond, there are two things you will want to consider: their size, and their color. Smaller, more colorful breeds may have an easier time maneuvering around the pond and discovering hiding spots, and they experience success this way. Larger breeds with darker coloring tend to find hiding in plain sight to be simpler.

What Are Some Live Foods You Can Feed Your Koi?

When it comes to feeding your Koi, live foods are simply better. They contain more protein, as well as lots of natural nutrients that are essential. Live food will improve your Koi fish’ energy, temperament, and color.


Mealworms are protein-rich, and full of other nutrients, as well. Many Koi will be happy to gobble them up; under the less-appealing exoskeleton is a lot of meat and flavor.

In fact, your Koi fish may not show interest in mealworms right off. The exoskeleton can prove a bit confusing for them at first. Most Koi fish are fast fans once they brave up, take a nibble, and discover the fleshy insides, however.


Koi fish will eat mosquitos and their larvae but there are other live foods that they tend to prefer. Of these, groundworms are undoubtedly number one. Unlike mealworms, groundworms are nice and fleshy all over.

To fish, this makes them full of appeal. Groundworms are the perfect soft and protein-filled fishy meal. Offer some groundworms to your Koi fish, and they will love you forever.

Live Shrimp

Koi fish are also known to enjoy live shrimp. They will give chase quickly, and gobble the shrimp up even faster. Live shrimp can be found at most pet stores, but groundworms are more affordable, in general. You may not wish to use shrimp as a primary live food source, but rather have it be supplemental.

Your koi fish will not say no to a stimulating snack!


Speaking of a stimulating snack… koi fish can eat crickets, that well-known backyard hopper. In fact, most Koi will already have eaten the few wild cricket unfortunates to hop or fall in the water. Though koi fish tend to prefer worms, they typically will accept crickets happily enough, as well.

girl looking into a pond
Goldfish and other smaller pond fish are better at clearing mosquitos than Koi

Koi Fish Also Eat:

Bloodworms and bloodworm larvae. Did you know that bloodworm larvae will actually help keep your pond clean? This, while serving as a protein-rich snack for your Koi. Win-win.

● Silkworm pupae. Do you find Koi fish beautiful? Silkworm pupae are said to bring out the beauty in Koi, making them more vibrant, and glossier.

● Other bug larvae. Koi fish consider just about anything food -even human foods, like watermelon or cereal. They will eat almost any bug larvae… though they prefer larger kinds, so they can see them easier.

● Tadpoles. Believe it or not, while Koi cannot tackle adult frogs, they have a definite taste for frog spawn and tadpoles. In fact, you can introduce tadpoles as a regular part of the diet of your Koi.

Final Thoughts

So, do Koi fish eat mosquito larvae? They do, but when it comes to keeping the mosquito population down, they are probably not the fish you will want to depend on. Instead, introduce some guppies, mosquitofish, goldfish… whatever you prefer! The mosquitoes in your yard will swiftly decrease in number.

Along with this, there are plenty of nutrient-rich, live foods you can feed your Koi fish besides mosquito larvae, including bloodworms, shrimp, earthworms, and more!