Guppies (Poecilia reticulata) are one of the most popular fish in the aquarium hobby because of their brilliant colors, lively personalities, and ease of breeding. In this care guide, we answer your most frequently asked questions about this simple yet beautiful species.
Discovered in South America around the 1860s, this hardy livebearer (or fish that gives birth to live young) was once used as pest control for mosquitos. They were eventually introduced to the pet trade and have been bred to display almost every color, pattern, and fin type imaginable. Nowadays you can find this amazing fish almost anywhere, ranging in price from $3 at your local pet store to several hundred dollars for a specialty strain from a distinguished breeder.
Guppies grow to an average of 2 inches long, so the smallest tank size we recommend is a 5-gallon aquarium for a trio of guppies. But given how quickly they reproduce, a 10- or 20-gallon aquarium would be more appropriate in the long run. If you plan on breeding them, start with a ratio of one male for every two to three females, and provide lots of cover (such as live aquarium plants) for the babies to hide in. Plus, use gentle filtration like a sponge filter so that the tiny fry won’t get sucked up.
Java moss is one of the easiest plants to grow and provides excellent cover for babies to escape being eaten by bigger fish.
A guppy-only tank is truly an astonishing sight to behold because of their flashy fins and energetic behavior, but you can easily keep them with other peaceful tank mates like cory catfish and neon tetras. Just avoid adding any aggressive fish that may nip their fins or eat them, such as tiger barbs or bala sharks.
Guppies look great in a planted, community tank with other peaceful tank mates.
Like many livebearers, guppies enjoy pH levels at 7.0 or greater. They also like hard water with good amounts of calcium, magnesium, and other essential minerals. If you live off well water with high pH, you’re going to become one of the best guppy breeders ever. However, if your water is naturally soft, add Wonder Shell to your aquarium, and it will help raise your water hardness and add minerals to the tank.
Wonder Shells are often used to increase water hardness and mineral content for livebearers, shrimp, snails, plants, goldfish, and African cichlids.
An aquarium heater is recommended to keep the water warmer at 76 to 78°F, since these new lines of fancy guppies are not as resilient as the original species found in the wild. At this temperature range, your guppies should have an average life span of two to three years. If you raise the heat to 82°F, the fish will grow faster and make more babies – but they’ll only live for 18 months. If you lower the temperature to 72°F instead, their life span may increase to 3.5 years or longer, but they’ll take forever to reach adulthood and may only have babies every six months.
Guppies can be kept in a wide range of temperatures that will directly impact their life span and rate of reproduction.
Guppies are pros at begging for food, so owners often overfeed them, which can lead to constipation and other health issues. Feed adult guppies once or twice a day, as much as they can eat in one minute. If you are raising fry, you can increase the feedings to three to five times a day, but make sure that each meal is much smaller in amount so that you won’t foul the water with excess food. Guppies are not picky eaters and will even graze on algae growing inside the aquarium. We like to give ours a wide variety of foods, such as bloodworms, brine shrimp, flake foods, pellets, and Easy Fry and Small Fish Food.
This high-quality, salmon-based food was specially developed for guppies and other community nano fish. The easy-to-use squeeze bottle allows you to feed tanks fast and efficiently.
If you have at least one male and one female (or your female guppy originally came from a tank with males), then the answer is probably yes. Males are very colorful and have a modified anal fin called a gonopodium that looks like a pointy, horizontal stick under their bellies. Females are usually larger in size, less colorful, and have a fan-shaped anal fin behind their bellies. They give birth approximately every 30 days and will predate on their own young unless you provide lots of hiding spots for the fry.
The male guppy (on the bottom) has a stick-like fin under his belly, whereas the female guppy (on the top) has a fan-like fin just behind her belly.
If you want to make lots of babies, increase the amount of food you give them and do partial water changes more frequently to keep the water quality high. Once the fry start to show their colors (around two to three months old), you can give them away to friends, feed them to other fish, or try selling them to your local fish store. If you’re interested in selling guppies, we have a whole series on how to successfully breed fish for profit.
The unfortunate truth is that guppies sold in pet stores can be fairly weak. They’re highly inbred to get those amazing colors, mass-produced in many countries, and kept in very crowded conditions that make them more susceptible to disease. (For more details, see our article on why livebearers are becoming weaker.) As they’re shipped all over the world to wholesalers, distributors, and then your local pet store, they might pick up diseases at each stop along the way. By the time the guppies get to you, they may need a lot of care and attention. Be prepared to give them nice, clean water, a good diet, and possibly medications to treat illnesses and infections.
Based on our 10+ years of experience running a fish store and importing wild-caught species, we invest the time and money to treat all incoming fish with a trio of broad-spectrum medications that’s safe for shrimp, snails, and plants.
Despite some of these potential challenges, guppies are truly one of the best fish to keep for both beginners and veterans because of their stunning appearance, small size, and rapid reproduction. Do additional research, join a Facebook group for guppies, and talk to other people who are passionate about this species. If you learn to treat your guppies well, you’ll be rewarded with hours of entertainment from your action-packed, rainbow-hued aquarium.
To find out how often you need to do water changes on your guppy tank, download our free infographic that guides you step-by-step through the process.