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Home > Fish > 11 Amazing Facts About Guppies (Interesting & Fun)

11 Amazing Facts About Guppies (Interesting & Fun)

multi color guppies in aquarium

Guppies are one of the most widely available aquarium fish that can be found in nearly every aquatic pet store. These small and colorful freshwater fish are a favorite for beginners since they are highly adaptable and can live peacefully with many different species of small fish.

Since guppies are so common in the aquarium hobby, many interesting facts about these fish are overlooked. However, the guppy has plenty of amazing facts you probably never knew that have led them to be a popular pet fish.


The 11 Most Amazing Facts About Guppies

1. Guppies Are Tropical Fish

Many people assume that guppies are cold-water fish, but this is not true. Guppies originated from tropical waters in northeast South America where they inhabit small ponds and streams with shallow water.

People often mistake guppies for cold-water fish and can even be labeled as such in pet stores. This means that many people make the mistake of not providing their guppy with a heater when purchasing them from a store. As a tropical or warm water fish, the guppy requires a heater to thrive.

The fluctuating room temperatures that can become too cold for guppies can lead to disease, slow breeding habits, and even early death. Guppies will be most comfortable at a temperature ranging from 71 to 82 degrees Fahrenheit (22-28 degrees Celsius). Although guppies can indeed tolerate slightly colder temperatures than other tropical fish, it is not ideal in the long term.

guppy in aquarium
Image By: Zucky123, Pixabay

2. One of The Best Fish for Beginners

Guppies are adaptable, easy to care for, and generally healthy fish which makes them perfect for beginners. A bonus is that their small size allows them to be kept in smaller tanks, and a 10-gallon aquarium can be perfect for a group of 3 to 6 guppies.

Guppies are more forgiving of sudden water parameter changes, which gives beginners time to fix any mistakes that would otherwise kill more sensitive species of fish. Aside from their adaptability, guppies are quite cheap depending on the color and fin type, which makes it affordable to purchase a group of them.

3. Guppies Give Live Birth

Instead of laying eggs as most fish do, guppies give birth to live young which makes them live-bearing fish. The baby guppies are known as fry, and female guppies can give birth between 20 to 120 fry from a single spawn.

They are sexually mature as early as 4 months of age and they can begin mating with other guppies in the aquarium, which makes them prolific breeders that can multiply fast.

Image By; Pixabay

4. A Fish of Many Names

The guppy is a fish of many names, such as the millions fish, rainbow fish, or even the mosquito fish. These names are commonly used by both pet stores and breeders, but they are all used to describe the guppy.

The name “millions fish” is derived from their ability to breed quickly and triple their numbers in a span of a few months. The name “rainbow fish” comes from the endless colors that guppies can be found in, from orange, and red, to a light neon green color.

The name “mosquito fish” comes from their ability to eat mosquito larvae from the water’s surface, and they have quite an appetite for these pests.

5. Guppies Were Used to Help Fight Malaria

Back in 2014, there was an anti-malaria movement in southern India where guppies were used to combat malaria caused by mosquitos. This is another reason they earned the title “mosquito fish”, and the schools of guppies would happily eat thousands of mosquito larvae.

This was useful because mosquitos lay their eggs on the surface of the water where the larvae would spend their first days developing. Since mosquitoes transfer malaria, guppies were able to control the mosquito population by eating the larvae before they could develop into adults.

mosquito larve in the water
Image Credit: Marc Pascual, PixabayBy

6. Guppies Are Available In Endless Colors, Patterns, and Fin Types

Guppies might be cheap and readily available in pet stores, but that doesn’t make them plain or basic fish to own as many people believe. Guppies can be found in a range of different colors, fin types, and patterns.

Guppy breeders are always coming up with new variations that have different fins, colors, and patterns that cost more than standard types of guppies. From the fancy, swamp, Endler, and the fantail guppy, the variations are endless, and breeders are creating new varieties each day.

7. Male Guppies Are Smaller Than Females

Like with most species of fish, the male guppy is significantly smaller than female guppies, and males are known for being more colorful. Female guppies can reach a length of 2.4 inches in length, whereas male guppies are between 1 to 1.5 inches.

The most likely reason for female guppies to be larger than males is because female guppies will develop a large belly when they are pregnant, and their larger size makes their body suitable for this.

It is common to see female guppies developing faster than females, although they don’t have many interesting and unusual color patterns as seen in males.

two guppies in aquarium
Image By; panpilai paipa, Shutterstock

8. Guppies Were Used To Test Drinking Water In India

Guppies were used to test the quality of drinking water in India. This experiment happened because of people dying from drinking polluted water, and since proper laboratory equipment to carry out this test was pricey, people began using guppies as testers instead.

The guppies would be placed into the water well and checked on after a few days passed. If the guppies died, it would mean the water was polluted and contained pollutants that killed off the guppies, but if they were still alive, it would mean that the water was safe for the people to drink.

9. Female Guppies Can Store the Male’s Sperm and Mate Several Times

Guppies are quite prolific breeders, but even if you try to separate male and female guppies, you could still end up with a batch of fry and pregnant females even months later. This occurs because female guppies can store the male’s sperm for several months before using it to become pregnant.

This can happen multiple times, and it is the reason behind your female guppies suddenly becoming pregnant even without a male. If you have purchased female guppies from a pet store, these guppies could have still mated with males from the pet store tank before being purchased, and only getting pregnant a few months later.

guppies in aquarium
Image By: Jumpstory

Female guppies will also mate with different males in the tank, so the fry could come out in all sorts of colors or fin types depending on the type of male guppies the female mated with.

10. Guppies Are Schooling Fish

As a highly social fish, guppies enjoy staying in groups of their species. Guppies will form schools to carry out their social behaviors, and they can become stressed if they are kept in small groups or by themselves.

Usually, when keeping a school of guppies, you will need to have a good male-to-female ratio, as male guppies are notorious for harassing female guppies by chasing them around to mate. If you have too few female guppies in an aquarium, all mature males will begin to chase and harass the smaller group of females, causing these females to become stressed.

It is better to have more female guppies than males in an aquarium, or you can create a separate aquarium for both genders if you do not want any fry.

11. Guppies Can Live for Up To 5 Years

As adaptable and easy to care for as guppies are, fish-keeping mistakes can lead to your guppy’s early death. The average lifespan of a well-bred guppy is anywhere from 2 to 5 years of age.

Poor water quality, improper temperatures, high nitrate or ammonia levels, along with an inadequate diet and stress could cause an early death in guppies which is why many people see guppies as disposable and short-lived pets when in truth, they are not.

Red Scarlet or Chilli Endler Guppy_Pavaphon Supanantananont_shutterstock
Image By: Pavaphon Supanantananont, Shutterstock



Guppies are a popular pet fish for a reason, with their ability to adapt easily to an aquarium and have care requirements that are beginner-friendly. Even though guppies are seen as common fish in the hobby, the facts we have mentioned in this article show just how misunderstood yet amazing these small and colorful fish are.

Featured Image Credit: panpilai paipa, Shutterstock

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