Mosquito Fish vs. Guppy Fish – What’s the Difference?

There are plenty of similarities between mosquito fish and guppy fish. Mosquito and guppy fish belong to different genera and species but thrive in similar water conditions. If you are a beginner wanting to keep fish, you have to pick the one that’s easy to care for. 

Mosquito fish are aggressive, less social, and prefer to live alone in a tank. On the other hand, guppies are friendly fish. Also, mosquito fish are dull grey or brown while guppy fish come in a variety of colors.

Mosquito fish are slightly bigger, about 2⅞ inches long, while guppy fish are 2⅛ inches long. If you are contemplating which fish to keep as a beginner between the two, I’d suggest guppies. Unlike mosquito fish, guppy fish are schooling and shoaling fish. Caring for them is also relatively easy. See other differences between mosquito fish and guppy fish below.

Mosquito fish vs guppy fish

Mosquito Fish vs. Guppy Fish: Differences

Here is a summary of the differences between mosquito fish and guppy fish:

Mosquito FishGuppy Fish
Lifespan of 1 – 1.5 years Lifespan of 2 – 3 years
Size: Female 2⅞  inches long. Male  1½ inches longSize: Female 2⅛ inches long Male  1¼ inches long 
Origin: North and Central America, Barbados and Mississippi river basin Origin: South America; Caribbean 
Breeding season: Every summer producing up to 100 offspring.Breeding season: Throughout the year, can double its initial number in 3 months
Appearance: Tan olive below and pale yellow above with dark spots on the scales. The males have blue shimmer on the sides.Appearance: They come in an array of bright rainbow colors. Males are more colorful and vibrant than female guppies.
Colors: Tan olive upper part and pale yellow lower part Colors: Variety of bright colors 
Behavior: Not sociable. They prefer to be kept on their ownBehavior: Very friendly, and can be kept with a variety of tankmates like platy fish

Based on the observations of both mosquito fish and guppy fish, here are their differences:

Guppy fish are slightly smaller than mosquito fish

When it comes to the size of these two fish, the difference is small and difficult to notice. But a keen aquarist will pick out the difference. Mosquito fish have slightly bigger bodies than guppy fish. That is because female fish are usually less active and thus have a slower metabolism than male fish.

A male mosquito fish grows up to 1½ inches long, and female mosquito fish grow to about three inches long under controlled conditions. But for guppy fish, the male grows up to 1¼ inches long, and the females grow up to 2⅛ inches long.

Guppies occur in many colors, while mosquito fish colors are limited

When it comes to appearance, female mosquito fish are mostly tan olive above, pale yellow below, and dark-spotted scales around the edges. The males have blue shimmer on the sides. 

On the other hand, guppy fish come in an array of bright rainbow colors, another good reason for keeping guppies. However, male guppies are particularly more colorful than female guppies. They can keep your aquarium bright and glowing with different rainbow colors. 

Guppies are more social than mosquito fish

Mosquito fish are also secluded fish, and they like to be kept in the tank by themselves. They do not like tankmates. Therefore, when it comes to mingling and playing with tankmates, mosquito fish are less social, while guppy fish are more social. 

On the other hand, guppies can live more peacefully with tank mates than mosquito fish because guppies are both schooling and shoaling fish. Guppies are social and can be kept with other less aggressive fish species in an aquarium. 

But before keeping another species with guppies, make sure they are compatible tankmates.

Guppy fish have a longer life span than mosquito fish

Guppy fish live longer than mosquito fish. Guppies will live approximately 2-2.5 years, while mosquito fish will live for about 1-1.5 years. You should provide a clean and healthy environment for your fish to have a long lifespan. 

A clean aquarium means weekly water changes, using an aquarium filter to increase the oxygen supply in the tank, and feeding the fish at least once a day.


Guppy fish are native to South America and the Caribbean and are primarily found in still and flowing water while mosquito fish are native to North and Central America and can be found in the Mississippi river basin. They are commonly found in ponds, ditches, and lakes.

Guppies breed anytime but mosquito fish breed seasonally

When it comes to breeding, guppy fish can breed anytime throughout the year, while mosquito fish depends on the seasons. For instance, guppy fish breed monthly and can double their population in three months. 

However, mosquito fish rely on summer to breed. That is when the temperatures are higher and favor their reproduction. Female mosquito fish can produce up to 6 young ones every season; that’s almost 100 mosquito fish offspring.

Can guppies breed with mosquito fish?

Keeping the guppies and mosquito fish together is a twist that’s hard to maintain; what about breeding them?  No, you cannot breed guppies with mosquito fish. They belong to different genera and species. Guppies belong to the genus Poecilia and mosquito fish to the genus Heterophallus.

Guppies are commonly bred with other fish like Endler and Mollies. Crossbreeders experimented with breeding mosquito and guppy fish, and it worked. But the young hybrid fish fry produced did not survive. The hybrid fish fry developed health complications after birth and died eventually.

However, if you keep male guppy fish in the same tank as female mosquito fish, they will try to mate just like most animals. That does not mean that they are sexually compatible. The fish might successfully breed, but the offspring will not survive after birth.

To avoid fry in the two fish, keep them in separate tanks or keep the males together if you do not want to breed them. If you’re going to breed them, keep the guppies with their mates separately and the mosquito fish with their mates in a different tank. Otherwise, keep them together, but don’t expect fish fry in your aquarium. 

Do mosquito fish eat guppies?

Mosquito fish do not eat guppies. They are both omnivorous, and they feed on mosquito larvae. A mature female mosquito fish and guppy fish can feed on lots of mosquito larvae per day. You can also keep guppy fish and mosquito fish to control mosquitos in abandoned pools and home backyards.

Mosquito and guppies are small-sized fish that are generally friendly, calm, and peaceful. You can keep them as tankmates, and they won’t harm each other. However, keeping them in a small tank can be challenging because of the male mosquito fish’s irritability.

Mosquito fish profile

Mosquito fish originated from North and Central America, the Mississippi river basin, Illinois and Mexico. They can survive in both brackish and fresh water in ponds and aquariums. Mosquito fish grow up to approximately 3 inches long. 

Their bodies usually have three colors: tan olive in the upper part, pale yellow lower part, and dark spots on their scales. The male mosquito fish have a blue blemish on the sides.  

Mosquito fish require little care and maintenance. The tank water temperature for mosquito fish should be between 33°F and 104°F and have a pH of between 6.5 – 8.0. Keep chloride and insecticidal sprays away from their tank because chlorinated water can suffocate and kill them.

Being omnivorous, they feed on mosquito larvae. Mosquito fish are among the best for mosquito control in homes, especially in outdoor ponds. A mature female mosquito fish can feed on hundreds of mosquito larvae and other aquatic insects in a day.

It’s easy to note the difference between male and female mosquito fish. Females have slightly bigger bodies with round anal fins, while males are smaller with pointed fins. Mosquito fish are also known to be fin nippers, and as they mature, they develop a biting behavior. 

Their tankmates should be fish that are pretty much aggressive and fast swimmers to match their energy. Do not keep mosquito fish with guppies or mollies in the same tank because of their fin nipping habit. Mosquito fish are okay if you keep them alone in a tank. 

Use a minimum tank size of 10-gallons to keep mosquito fish. If you give them the correct care and requirements, mosquito fish will have a life span of 1-1.5 years.

Guppy fish profile

Guppy fish is one of the most common freshwater fish kept by aquarists. They originated from South America and the Caribbean. A mature guppy fish is approximately 2.8 inches and comes in various bright colors; the males are more colorful than the female.

Guppies grow healthy and thrive in aquarium water temperatures between 24 and 30 degrees Celsius and a pH of 6.8 – 7.6. Feed guppies twice a day. Give them mosquito larvae, brine shrimps, or dry flakes.

Most importantly, remove any food leftovers from the water every week to avoid the accumulation of toxins that can kill the fish.

You should clean the tank weekly and change 30 – 50% of the water depending on the tank size for guppy fish. If you remove the guppies from the tank, place them in similar water conditions as the aquarium to avoid water variations that could stress the fish.

Unlike mosquito fish, guppies have a  fast growth rate with a life span of between 2-3 years and can extend if given proper care and a healthy environment. They are usually peaceful, friendly, and calm fish. You can keep guppies in an aquarium to decorate your home or office space or control mosquitoes in your pond.

Being peaceful and friendly, guppies are compatible with small-sized and less aggressive fish such as platy, neon tetras, and mollies. They like playing around with other friendly fish and will school when they sense an enemy or danger.

Therefore, keep three or more guppies together. Also, remember that the minimum tank size for guppies is 5-gallons.

Guppies breed monthly and can double their number in three months. If you keep them for breeding, a 40-gallon tank is the bare minimum size. Otherwise, it’s advisable to keep a female or male-only fish aquarium to prevent overcrowding in your tank.


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