Guppy Fish Species Profile

Guppy fish with orange fins swimming in tank

The Spruce / Adrienne Legault

Guppies have been a staple of the aquarium hobby for generations. Originating in tropical pools in South America and the Caribbean Islands, these fish are now available in a wide variety of colors that have been produced by selective breeding at fish farms. Many guppy keepers may start out with only one or two fish, but being live-bearers with long-term sperm storage, you may be in for a full tank before long.

Species Overview

Common Name: Guppy 

Scientific Name: Poecilia reticulata

Adult Size: 2 inches

Life Expectancy: 2 to 3 years

Characteristics
Family Poeciliidae
Origin Native to South America, pet fish are captive-bred
Social Peaceful
Tank Level Top, mid-dweller
Minimum Tank Size 10 gallon
Diet Omnivore
Breeding Live-bearer
Care Beginner
pH 6.5 to 8.0
Hardness 100 to 150 mg/L (6 to 8 dH)
Temperature 68 to 78 F (20 to 26 C)

Origins and Distribution

The guppy has been captive bred for over 100 years, but originally came from South America. They are named for Robert John Lechmere Guppy who collected these fish on the island of Trinidad in 1866. They are native to freshwater streams in the north of South America, including Surinam, Guyana and Venezuela, and the Caribbean islands, including Barbados, Trinidad and Tobago. Now, they have been introduced to every continent but Antarctica and can be found in many warm waterways around the world

Colors and Markings

There are countless color varieties of guppies. Males have more vibrant colors than females, and have longer caudal and dorsal fins. Depending on the variety, some guppies have short, rounded tails, some "V"-shaped and others can have an elongated tail half the length of their body. Tail fins may have a marbled or striped appearance, or the fish may be all one or two colors. Whatever color combination you can dream, there is probably a perfect guppy for you.

Many websites and some pet stores will offer "select" or "unique" varieties found nowhere else. Many times, these strains are the result of serious inbreeding and produce fish with compromised immune function and shorter life spans. Try to stick to the mainstream varieties with well-established lineages. If you end up breeding two different strains, you may be surprised how the color variations mix.

Tankmates

Guppies are peaceful, easy-going community fish and play well with a mix of other non-aggressive fish species. You may want to keep them with similar, live-bearing fish, such as platys or mollies. Other good tankmates include small fish such as neon tetras or zebra fish. Keep in mind that any fry spawned from an active guppy female may be dinner for other fish in the tank, so having smaller tankmates will ensure more fry survive.

Many guppy keepers often opt for a guppy-only aquarium. You are welcome to mix different varieties of guppy in the same tank.

Guppy Habitat and Care

Guppies are great beginner fish. They are low maintenance and can tolerate some beginner mistakes. A bigger tank size is recommended since guppies are very active fish. They thrive in an aquarium with plants and soft décor items.

In order to keep your population from exploding, it is strongly recommended that you separate males and females in different tanks. That will help prevent a population explosion. Guppy females can store sperm for multiple spawns, even after separation from males, so once a female has been with a male she may have multiple batches of babies. Tank dividers are okay as a temporary solution, but many of these flimsy, plastic dividers are usually not enough to keep fish separated. Two separate tanks will keep unwanted spawning to zero.

Guppy Diet and Feeding

Guppies are omnivores and do well on a variety of commercially available feeds. Even though guppies are small in size, pelleted diets, called micropellets, are the best choice since they hold onto their nutrition longer than flakes. You are welcome to add supplements, such as frozen fish foods, but no more than once or twice a week. The complete pelleted diet is best for most pet fish species.

Depending on your aquarium's temperature, and the other tank inhabitants, you may feed your fish once or twice a day. Always start with a little bit of food, and when it has all been consumed, add a little more. Repeat for a few minutes and use this time to check out all of your fish. Feeding time is a great time to see if any of your fish are acting odd or sick.

Gender Differences

There are a few gender differences you will need to identify to keep your male and female populations separate. Males tend to be smaller and more vibrantly colored. Females tend to have a brown coloration and are larger and rounder.

Three guppy females and two males, with some young
Three large female guppies and one male (bottom right)  underworld/Getty Images

On the underside of the fish, the anal fin of the male is long and thin and tapers to a point. The anal fin on the female guppy is larger and triangular or fan in shape. As the male guppies grow, the body will develop coloration that does not occur on the female's body. Guppies are sexually mature in about 2-3 months, and you should be able to identify the differences between genders by a month of age, if you wish to separate them. Female guppies first produce offspring at 10–20 weeks of age, and they continue to reproduce until 20–34 months of age. 

Breeding the Guppy

Many beginner hobbyists will start with only one female guppy and suddenly have a swarm. Since female guppies can store sperm, it only takes one insemination by a male for a few spawns to be born. In order to prevent your aquarium from maxing out its stocking capacity, it is always best to separate male and female guppies.

Guppies are live-bearers, so the female will give birth to 10-50 wiggling fry per spawning. Many times, the newly born fry will be eaten by other fish in the aquarium, so if you want to save any fish, keep them in a separate tank or breeding box. Heavily planted aquariums will also give the babies places to hide and survive.

After breeding together many generations of the same population, you may notice an increased number of fish with congenital abnormalities, such as crooked spines or shortened lifespans. Inbreeding is a common occurrence in isolated fish populations with a simple solution: add more diversity! Many hobbyists will elect to trade fish with a fellow guppy keeper, or you can purchase new fish to add to your aquarium once they have cleared quarantine.

More Pet Fish Species and Further Research

If you like guppies, and you are interested in suitable tankmates, check out these other species:

Here are more suggestions for low-maintenance freshwater fish for beginners.

FAQ
  • What are the different guppy tail types?

    Guppies have been bred to have a variety of tail shapes, as well as many different color combinations. Some of the most common tail types you'll see at the pet store include:

    • Fantail: This is a flowing tail in the shape of an open fan.
    • Veiltail: The veiltail guppy has a longer, more flowing tail than the fantail guppy.
    • Delta: This tail is similar to the fantail but a little larger and more rounded.
    • Flagtail: The flagtail guppy has a slightly shorter, narrower tail than the fantail.
    • Double Swordtail: This striking tail has two sword-shaped protrustions, one upper and one lower.
    • Top Swordtail: These guppies have just one "sword," and it's on top.
    • Bottom Swordtail: As you can guess, these guppies have a "sword" on the lower part of their tail.
    • Lyretail: These guppies also have an upper and lower protrusion on their tails, but the lyretail is much more rounded and flowing than the swordtail.



  • How long do guppies live?

    You can extend your guppy's life by feeding it a good diet, watching for disease, and maintaining balanced aquarium water, but as a general rule, guppies live between two and three years, with females generally living longer than the males.

  • Do I need a heater in my guppy's tank?

    As a general rule, you need a heater to keep your guppies healthy. They prefer water temperatures in the 70s, and few homes are warm enough to provide that without an immersible heater in the tank. Monitor water temperature daily and adjust the heater as needed to keep your fish comfortable and healthy.

  • Does a guppy tank require a filter?

    Your aquarium definitely needs a filter to remove impurities and harmful chemicals from the tank water. Without a filter, aquarium water tends to quickly become filled with pollutants from uneaten food and fish waste, and your fish can become ill or even die from this harmful water. There are many types of aquarium filters available to suit any budget, so talk to the fish expert at your local aquarium shop or pet store if you are uncertain as to which filter is best for your tank.