Guppy Fish Care Sheet | PetMD

Guppy Fish Species Overview

Native to South America and the Caribbean, guppies are one of the most popular freshwater aquarium fish species. This care sheet outlines basic care needs for a variety of guppy species, including: 

• Fancy guppies

• Yin yang guppies 

Guppies are highly social and should not be kept individually. Instead, guppies thrive when kept in groups of three or more fish from the same species. 

Guppy Fish Characteristics 

Guppy Fish Supply Checklist

To keep a guppy happy and healthy, pet parents should have these basic supplies on hand: 

Guppy Fish Habitat

Choosing the Right Enclosure 

A single adult guppy should be housed in a 5-gallon aquarium or larger. For each additional guppy in the tank, provide at least two extra gallons of tank space. For example, a group of three guppies will need at least a 9-gallon aquarium. 

Guppies can leap up to seven times the length of their body, so their aquarium must be secured with a fitted lid or canopy to prevent fish from attempting to escape and getting injured.  

Always provide the largest habitat possible, especially as water parameters are less stable in smaller tanks compared to larger ones. 

Selecting Tankmates 

Guppies are best kept with other guppies because they are highly social. Guppies should never be housed alone and should instead be kept in groups of at least three fish from the same species. If choosing to house male and female guppies in the same tank, provide two to three females for every male. If males and females are housed together, expect them to breed. 

Schools of guppies can also be kept with other community fish with peaceful temperaments, including: 

• Danios 

• Gouramis 

• Mollies 

• Platies 

• Rainbowfish 

• Rasboras 

• Swordtails 

• Tetras

While both species are popular pets, guppies should not be kept in the same aquarium as goldfish. Goldfish prefer cooler temperatures than guppies. Goldfish can also grow quite large in adulthood and swallow guppies.  

New tank mates must be introduced to an aquarium gradually, and pet parents should remember that their tank’s ammonia, pH, and nitrate levels will change when a new fish is introduced. These parameters need to be monitored carefully after adding new fish.   

Fish should not be kept in overcrowded aquariums, as these conditions often lead to stress and disease in the tank. 

Filtration 

A filter system is an essential component in any aquatic habitat. In addition to keeping tanks clean, filters remove harmful toxins like ammonia from the aquarium’s water and also add oxygen to the water so fish can breathe.   

Power filters (also known as “hang-on-back” filters) and external canister filters are recommended because they offer effective mechanical, biological, and chemical filtration and do not take up any space inside an aquarium. Generally, guppies prefer water with slow to moderate circulation. 

Tip: An aquarium’s filter should be powerful enough to process all the water in the tank at least four times an hour. For example, a 20-gallon tank should ideally have an aquarium filter with a flow rate that’s at least 80 gallons per hour (GPH). If only 50 or 100 GPH filters are available, pet parents should always size up and purchase the 100 GPH option.  

Water Health 

Pet parents should test their aquarium’s water regularly to ensure its pH, ammonia, nitrate, and nitrite levels are stable and within a safe range. An aquarium test kit can be used to measure key water parameters quickly and accurately. 

Many guppy species benefit from the addition of freshwater salt to their aquarium. If freshwater salt is added to the tank, the water’s specific gravity should be kept at 1.004 and should not change more than +/- 0.001 in 24 hours. Pet parents must research the needs of the specific species of guppy they’re caring for before adding freshwater aquarium salt to the habitat.  

A hydrometer or refractometer (salt level tester) should be used to measure the salt concentration and specific gravity of the aquarium’s water. 

Temperature 

Guppies prefer water temperatures from 72 to 82 F. The water’s temperature should not fluctuate more than 2 degrees up or down in 24 hours.  

Pet parents should install an aquatic heater that’s controlled with a thermostat in their aquarium to keep the water’s temperature in the ideal range. An aquarium thermometer should be used to check the tank’s water temperature daily. 

When selecting a heater for their tank, pet parents should keep a few things in mind: 

• Some modern heaters have built-in thermostats, while others need to be paired with a thermostat that’s purchased separately. 

• As a rule of thumb, aquarium heaters need between 2.5 and 5 watts of power for every gallon of water in a tank. This means that a 10-gallon tank needs a 25- to 50-watt heater. 

• Larger aquariums with a tank volume of at least 50 gallons may need two small heaters, placed on opposite sides of the tank, to prevent cold spots from developing in the water. 

Decor and Accessories 

Substrate

The bottom of a guppy’s tank should be lined with 1–2 inches of freshwater sand or gravel. Be sure to rinse the substrate with clean, running water before adding it to the tank.   

Guppies spend most of their time swimming at the top and middle parts of an aquarium and generally don’t linger near their substrate. 

Generally, sand is better for anchoring plants than gravel. 

Aquariums need about 1½ pounds of substrate for each gallon of water in the tank. For example, a 10-gallon tank will require about 15 pounds of substrate to create a 1- to 2-inch layer.   

Plants, Rocks, and Hiding Decor

Guppies need plenty of hiding places to feel safe and secure in their aquarium. Either live or artificial plants can be used, but live plants will provide fish with an extra food source. 

Guppy grass, java moss, and duckweed are all hardy and guppy-safe.

Plants should be arranged around the perimeter of the aquarium so that the fish still have an open space to swim. 

Guppy Fish Cleaning and Maintenance

Pet parents can maintain the condition of their guppy’s tank by performing routine water changes (no more than 10–25% of the aquarium’s total water volume) every two to four weeks. Uneaten food should be removed from an aquarium daily with the help of a fine mesh net. 

Draining and replacing the aquarium’s entire water volume should be avoided, as doing so will remove  beneficial bacteria in the tank that keep the habitat’s ecosystem healthy.  

Most aquariums will need a full cleaning once a month, depending on the number of fish/invertebrates in the tank. Learn how to clean a fish tank with these step-by-step instructions.

Guppy Fish Diet and Nutrition

As omnivores, guppies should be fed a varied diet of fed flakes, pellets, freeze-dried, and frozen foods formulated for freshwater fish. To stay healthy, guppies need variety in their diet and should not be fed the same food every day. 

Guppies need to be fed one to three times per day (depending on size/species) and should not be offered more food than they can consume within one or two minutes. Frozen foods must be thawed before feeding. 

Remember: Pet parents should never use a microwave to thaw or warm frozen food, and never offer food that’s still frozen to a pet. Frozen food that is not consumed should never be refrozen for future use, as this encourages bacteria to form in the food. 

Considerations for Guppy Fish

• After a new fish/invertebrate or new equipment is added to an aquarium, it’s important to test the tank water’s quality once a week for at least two months to ensure its pH, nitrite, ammonia, nitrate, carbonate, and general hardness levels are in the ideal range.  

• If the tests’ results are safe and consistent after two months, decrease water testing to once a month. 

• Water test kits expire and should be replaced yearly.  

Pet parents should monitor their aquarium’s water level and top it off as needed. Before being added to an aquarium, water must be treated with a water conditioner to remove toxic chemicals like chlorine, chloramines, and heavy metals.  

An aquarium’s filter, water temperature, and other equipment should be checked daily to ensure they’re working properly. Filter media should be replaced monthly or rinsed in old tank water during water changes, depending on the water condition and the number of fish/invertebrates in the tank. 

Pet parents should follow the use, care, and maintenance instructions provided by the manufacturer of their filter system.  

Do not use hot water, bleach, or chemicals while rinsing filter media. This will kill the beneficial bacteria that helps keep aquatic habitats safe, clean, and stable.  

Avoid replacing all the filtration media in an aquarium at the same time, as this can also remove beneficial bacteria from the tank. 

Guppy Fish Veterinary Care

Annual Care

In a properly maintained tank of appropriate size, in which you perform your own water quality tests and water changes weekly, it is OK to only consult with a veterinarian if there is a problem with your guppy. While a guppy can be transported to a vet, it’s recommended that you find an aquatics veterinarian who will more than likely make house calls, as transport is a major stress event for fish.

Signs of a Healthy Guppy

• Bright coloration

• Regular and active swim pattern

• Schools when appropriate

• Intact fins with no discoloration

• Full range of fin motion, equal on both sides

• Large appetite

When to Call a Vet

• Bulging eyes with or without a color change

• Changes in coloration

• White growths/spots of any kind

• Abnormal or lethargic swim pattern such as circling, listing to the side, or staying on the top or bottom of the tank

• Receding fin edges with or without discoloration at the edges

• Decreased appetite for more than a day

• Itching

• Rapid breathing, potentially with flared gills

• Gill color changes, usually pale or red

• Presence of lumps/bumps/masses

• Bloated appearance with scales flared outward instead of laying flat

• Swimming separately from other guppies consistently

Common Illnesses in Guppies