Guppy: Species Profile

Category: Livebearers

Common Names: Guppy

Scientific Name:Poecilia reticulata


Minimum Tank Size: 10 Gallons

Care Level: Easy

Temperament: Peaceful

Max Size: 3 Inches

Temperature: 68-80 F

pH: 6.5-8.0

Tank Level: Middle to Top

Colors: Pretty much all of them

Diet: Omnivore

Breeding: Very Easy

Guppies in freshwater aquarium

Species Overview

Guppies are popular because they come in a near-endless array of colors and patterns. They’re also active fish, making them fun to watch in a tropical aquarium.

Breeders love guppies because they produce offspring quickly, with females having as many as 50 fish per month.

The guppy is an excellent fish for beginner fish keepers because they’re easy to care for and don’t cost a lot of money.

Like any fish, they have specific parameters that you’ll need to keep their tank within. However, it doesn’t take a lot of effort to learn about them, and guppies are relatively hardy should the parameters briefly dip out of their preferred range.

Beautiful Guppy Isolated on Black Background

Distinguishing Features

It’s unlikely (not to mention illegal) that you’ll catch a guppy in the Amazon River and take it home with you. However, if you see a guppy in the wild, you might not even recognize it.

That’s because wild guppies have diluted colors, with primarily gray tones. They also have a smaller tail and caudal fin.

Thanks to selective breeding practices, the guppies you’ll encounter at your local pet store are the polar opposite. They typically have a massive dorsal fin, with males having an even larger fin than females.

Guppies in captivity also have a long, flowy dorsal fin, a shorter but still showy anal fin, and delicate pectoral fins by their heads.

Nevertheless, their tail (the caudal fin) often steals the show when people admire guppies. A few of the many different guppy tail variations include:

  • Fan
  • Top sword
  • Spade
  • Spear
  • Round

Furthermore, you can encounter guppies in nearly every color imaginable, including:

  • Red
  • Yellow
  • Blue
  • Purple
  • Pink
  • White

Many guppy species have iridescent properties with spotted tails. Because people are attracted to their colors, it’s more common to find multi-colored guppy fish than solid-colored ones.

Because there are hundreds of guppy types, the variations within this species are vast. For example, the common guppy has a body that tilts slightly downwards, whereas the double swordtail guppy has an almost pin-straight body and a forked tail.

Close up shot of orange, black, and silver guppy


Guppy fish are from South America, where over 300 variations exist. You can frequently spot them in the Amazon River and its tributaries, although you can also find them in freshwater rivers in the following countries:

  • Venezuela
  • Brazil
  • Barbados
  • Guyana
  • Trinidad and Tobago

Because of their array of colors and designs, people sometimes call guppies “rainbow fish.” They also quickly populate any freshwater area with suitable water parameters, getting the name “millions fish.”

Although guppies prefer freshwater, they won’t die if they encounter brackish water.

It’s also common to find them congregated in shallower areas with slow-moving water. That’s because their small size makes it easy for them to get swept away in fast-moving water or eaten by prey in deep places.

Guppies most commonly live in muddy or sandy soil, often with small rocks mixed in. They don’t mind cloudy water in their natural environment, given that mud kicks up around them.

However, cloudy water in a tank is a sign of waste build-up. Therefore, it can lead to illness and death for your guppy.

Live plants are an essential aspect of the guppy’s natural habitat. They serve as a place for guppies to grow into adults, hide from predators, play, and rest.

Some of a guppy’s favorite types of live plants include:

  • Java moss
  • Christmas moss
  • Water wisteria


Guppy fish vary in size according to the species, but all fall into the small fish category.

Females are significantly larger than males, averaging 1.2 to 2.4 inches long. In contrast, male guppies typically only grow to 0.6 to 1.4 inches.

You can expect your guppy to reach adult size by the time it turns six months old.

Although sex and genetics play a significant role in how large your guppy will grow, nutrition and water quality are also important.


We hate to break it to you, but your beloved guppy will only live for an average of 1 – 3 years in captivity. If that sounds too short, you can take comfort in knowing that this timeframe is a lot longer than most guppies live in the wild, given they’re low on the food chain totem pole.

Nevertheless, if you take optimal care of your guppy, they may live for as long as five years.

It’s best to lower your guppy’s water temperature as they get older to keep their environment stress-free as they age, which can increase their lifespan. That way, you’ll encourage their metabolism to slow, keeping them more comfortable.

Guppys in freshwater aquarium


Luckily, it’s easy to tell the difference between male and female guppies. And because of how fast-growing these fish are, you can check their sex when they’re only one week old.

The three ways to know whether you’re looking at a male or female guppy is by assessing the following:

  1. Fins
  2. Coloring
  3. Body shape

Take note that it’s crucial to make this comparison between guppies of the same species. Otherwise, you could accidentally mistake a male for a female or vice versa.

A longer dorsal fin (the fin on top of the fish) is a classic sign of a male guppy. You can also look at their tail, which often has more patterns and bolder colors than females.

The body size is also a sure-fire indicator of whether you’re looking at a female or male guppy, with males being significantly smaller in size. As a result, males have narrower, thinner bodies than females.


Overall, guppies are peaceful fish. They do well in tanks with other guppies as long as they have enough space.

Furthermore, you can feel at ease having guppies share a tank with other schooling fish of a similar size.

That said, if a guppy shows signs of aggression, it’s often a male. That’s because males will vie for a female’s attention, picking on other guppies to make themselves stand out.

Tank Parameters

Ensuring you maintain the proper tank parameters for your guppy is essential to help them live a long and healthy life. So, below are the items you should prepare before welcoming a guppy into your family.

Minimum Tank Size

Adult guppies require over one gallon of water per fish, meaning that you can safely have three guppies living in a five-gallon aquarium.

Nevertheless, we encourage you to offer your guppies even more space, especially if you have both sexes living together. Guppies are prolific breeders, so the inevitable moment will happen when they reproduce.

Many people only fill their tropical fish tank with guppies because they’re colorful and energetic.

However, if you want to introduce other fish, talk with your local fish vendor to determine how many extra gallons of water you should offer them.

Green Body With Orange and Black Fins Guppy

Water Parameters

Your aquarium water can make or break the quality of your guppy’s life. So, be sure to test for and stay within the ranges below.


Guppies can tolerate water between 65 to 90 degrees Fahrenheit. However, we recommend keeping your guppy’s water between 74 to 82 degrees, as they may die if they spend extended time in temperatures outside this range.

Water that’s too warm reduces the amount of dissolved oxygen in the water. It also increases the rate at which bacteria forms and toxins develop from food waste and excretions.

In contrast, if you keep your guppy’s water temperature too cool, they’ll likely suffer from diseases as a result of temperature stress.


We recommend maintaining your guppy’s tank pH between 6.8 and 7.6. Although your guppy will likely survive if the water temporarily falls slightly below or above this range, it’ll cause them excessive stress.

Furthermore, do not change the water’s pH too rapidly. Although changing the water from a 6.8 to a 7.6 is within a guppy’s adaptable abilities, the sudden change can cause them to go into shock, opening the opportunity for illness to strike.

The best way to check your tropical fish tank’s pH levels is by purchasing a test kit from your pet store. Then, check the water weekly.


It’s not necessary to maintain a certain level of salinity in your guppy’s water for them to achieve optimal health. On the contrary, salt can hurt their health.

Salt serves an important purpose for some fish to give them electrolytes and help them heal from certain diseases. So, if your guppy falls ill, adding salt to the water may help them recover.

However, on a day-to-day basis, your guppy will thrive in standard freshwater.

Tank Setup

Now that you know how to manage your guppy’s water, the fun part begins—setting up the tank! Before you stuff it full of colorful ornaments and substrate, though, keep the information below in mind.


In the wild, guppies often live in environments with mud bottoms. But because we know you don’t want to dump dirt in your aquarium, sand is an excellent substrate that’ll keep your guppy happy.

Sand’s fine texture makes it a gentle choice as a substrate. Many aquatic plants also do well growing in sand, and as you’ll soon learn, you should include live plants in your guppy’s tank.

Here’s the kicker, though—guppies spend much of their lives closer to the water’s surface. So, the substrate is more for your personal aesthetic enjoyment than theirs.

As a result, you can also use gravel, rocks, or other substrates.


Including decorations in your guppy’s tank is as fun for them as it is for you. Guppies appreciate hiding places, which decorations can offer.

However, there are two factors to keep in mind when choosing decorations for your guppies:

  1. They need plenty of open space to swim.
  2. They won’t spend much time around decorations at the bottom of their tank.

For these reasons, some people choose to forgo decorations and replace that space with live plants instead.

Guppies in freshwater aquarium


Offering your guppy plants—preferably live ones—is crucial to their wellbeing, given that this will mimic their habitat in the wild.

Plants are also a way to reduce your guppy’s stress, especially if any tank mates decide to start picking on them.

In addition to offering shelter, live plants also help your water stay clean by feeding off nitrates and helping your water’s parameters remain in balance.

When choosing live plants for your guppy, find varieties that grow tall or float on the surface. That way, your guppies will be able to access them at their ideal level of the tank.

Although it’s tempting to pack your tank full of plants, it’s equally important to offer your guppies space to swim. So, striking a balance between the two is crucial.


It’s essential to include a light in your tropical fish tank, as guppies rely on it to know when it’s day and night.

Even though guppies don’t have eyelids, they still sleep when it’s dark, as they have a circadian rhythm like humans.

Therefore, set your tank’s light on a timer or remember to shut it off at night and turn it back on in the morning. Otherwise, you could create some stressed, sleep-deprived guppies that’ll be more prone to picking up a disease.


Filters are an absolute must for guppies. Unlike in the wild, tropical fish tanks can’t receive freshwater inflow.

There are three main types of filters you’ll encounter when doing your shopping:

  • Biological
  • Chemical
  • Mechanical

Biological filters promote healthy bacteria growth. These filters work by literally eating nitrates, ammonia, and nitrites.

In contrast, chemical filters remove chemicals in your tank’s water, and mechanical filters remove physical pieces of waste.

For this reason, it’s wise to set up your guppy’s tank with all three of these filters.


Guppies are warm water-dwelling fish. Because it’s unlikely you keep your home as hot as they like it (between 74 and 82 degrees), installing a heater is a must.

When searching for the appropriate heater for your tank, we recommend aiming to purchase a heater wattage that’ll cover five watts per gallon of water.

So, if you have a ten-gallon tank, you should purchase a 50-watt heater.

In addition to the heater, you should keep a thermostat in your tank. That way, you can check the temperature whenever you’re feeding your fish.

Heaters won’t last forever, and they sometimes malfunction, so a thermometer will ensure you act as quickly as possible if your tank’s water temperature gets wonky.

Black Orange Gold Guppy


Guppies have a diverse diet in their natural habitat. Some of their favorite foods include:

  • Small invertebrates
  • Algae pieces
  • Mineral particles
  • Insect larvae
  • Diatoms
  • Plant fragments

Understandably, these aren’t items you store in your pantry for a rainy day. For this reason, most people choose to purchase dried guppy food from their pet store.

While this food offers well-rounded nutrition for your pet, it’s not stimulating for guppies day in and day out. Therefore, we recommend adding variety to their diet by providing them treats such as unsalted:

  • Peas
  • Cucumbers
  • Lettuce

Regarding how much to feed your guppy, the rule of thumb is to give them food twice per day totaling about one-eighth of their body weight for each feeding session.

Because that’s understandably a challenging number to wrap your head around, here’s another method—let them eat as much food as they can in one minute, then scoop up the remainder and throw it away.

Yes, it sounds wasteful. But before long, you’ll have a good feel for how much food your guppy can consume in a minute.

Not only will you save your guppy from obesity problems by monitoring their food intake, but by removing excess food, you’ll also prevent potential diseases that can crop up from food waste.


Guppies are a joy to breed because they spawn quickly. It’s also fun to see the different color patterns the baby fish, called fry, will have.

Many guppy owners inadvertently breed their fish because they have males and females in the same tank. But to ensure you maximize your chances of fry, we recommend placing one male in your tropical fish tank for every two or three female guppies.

Because adult guppies will eat their young, it’s crucial to place plenty of vegetation in their aquarium so they can hide.

Furthermore, replace your filtration system with a sponge filter. That way, you won’t have to worry about fry getting pulled out of the water as “debris.”

That said, some people like to get more selective with how they breed. For example, you might want to breed your guppies based on one or more of the following traits:

  • Color patterns
  • Tail shape
  • Size

You can get as fancy as you want by mixing and matching different types of guppies to create a unique set of fry.

Before placing these hand-selected guppies in a special breeding tank, add lots of low-growing plants and substrate at the bottom. That way, the fry can hide without as much fear of their parents eating them.

Female guppies have a gestation period between 26 and 31 days. Ideally, you should remove the mother from the tank after she gives birth so that she can’t eat her now fully independent babies.

Guppies in a Tropical Aquarium

Common Diseases

Like all fish, guppies can fall ill. The good news is that following the advice we share here will significantly reduce the chances of this happening, as poor water quality and unbalanced parameters frequently cause disease.

Nevertheless, if you notice your guppy acting off, below are some of the most common ailments that might be causing it.


Ick has several names, including “white spot disease” and “ich.” Regardless of what you call it, this illness results from an ectoparasite.

Signs that your guppy has ick include if small white spots appear on their body and they start rubbing themselves against objects in the tank. They may also stop eating.

Ick most commonly occurs when you introduce a new, infected fish to your tank. If you catch ick soon enough, you can heal your guppy by applying salt and ick medication to the water.

Fin Rot

Fin rot, which can also happen on the tail, is the result of flesh-eating bacteria. In some cases, it can also be from ammonia burns or fungus growing on fins that another fish bit.

Move your guppy to an isolated tank to get rid of fin rot. Then, treat the water with antibiotics or fungus medication, depending on the cause.

It’s also essential to change the water in the original tank to help rid the bacteria or fungus from the water.

Guppy Disease

As its name implies, guppy disease is a condition that primarily impacts guppies. The culprit is a protozoan parasite that latches on to the fish, making its way through its muscles and into the bloodstream.

It’s most common to find this parasite in guppies that live in tanks with too cold temperatures or poor water quality.

So, increasing the heat is the first step in getting rid of this parasite. To speed up your guppy’s recovery process, you should also apply special protozoan medicine to the water.

Potential Tank Mates

Guppies aren’t inherently schooling fish, but they’re not the kind of fish that like isolation either. For this reason, you should always purchase guppies in pairs, at a minimum.

Other fish species are also an excellent way to keep your guppy’s social life in good standing.

When assessing the best-fit tank companions for your guppies, you should aim for schooling fish that are a similar size as them. So, avoid large fish (they may eat your guppies), those notorious for being aggressive, and fin-nipping fish.

If that sounds like too many rules, below is a cheat list for excellent guppy tank mates:

  • Platies
  • Swordtails
  • Cory catfish
  • Mollies
  • Cardinal tetras

You can also add crustaceans to your guppy’s tank without worrying about starting a war. Snails, shrimp, and crabs are all excellent choices. Just don’t put a crayfish in your guppy tank, as they’ll feast on them.