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Freshwater Livebearers

Freshwater Livebearers

includes mollies, platies, swords, guppies, halfbeaks and variatus fish species

Most Freshwater Livebearers originate in North, Central or South America. They give birth to live young and readily adapt to changes in the water. Recommended for beginning aquarists.

Freshwater Livebearers

Freshwater Livebearers Facts

average adult size: 1 to 6+ inches long, depending on species
average life span: depends on species
diet: carnivore, herbivore or omnivore, depending on species
minimum aquarium size: 5+ gallons, depending on species
water temperature: 72-82°F


A well-balanced Freshwater Livebearer diet consists of:

  • Food may be flaked, pellet, frozen or live.
  • Avoid exclusive food which is not nutritionally complete.


Things to remember when feeding your Freshwater Livebearer:

  • Depending on species and size, feed small amounts 1-3 times daily, no more than fish will eat in 3-5 minutes.
  • Carnivores consume larger-size morsels once a day.
  • Herbivores prefer eating smaller pieces all day long.
  • Omnivores prefer a diet of both animal and vegetation matter.
  • Thaw frozen food before feeding.


  • Keep in an appropriate size aquarium; provide plants for hiding, various species may prefer sparse or thick vegetation.
  • Stable water quality, water temperature, and pH levels are critical to the health of the aquatic life. If you are unsure of your water quality or pH levels, Petco provides free water testing.


  • Freshwater Livebearers do best in groups of three or more of the same species.
  • Some species, such as mollies, do best in water with one teaspoon of aquarium salt added per gallon of water; test the salinity level of your water before adding salt.
  • Females are usually larger but less colourful than males.

Habitat Maintenance

Daily:check filter, water temperature and other equipment.
Weekly:check water quality at least once a week.
Monthly:change 10-25% of the total volume of water every 2-4 weeks, or as needed.
Introduce new inhabitants to the aquarium gradually.


Check Petco’s freshwater compatibility care sheet for species specific information.


Signs of a Healthy Fish

  • Clear eyes
  • Healthy appetite
  • Bright, even coloring
  • Clean in appearance

Avoid overcrowded conditions; they are a major cause of stress and disease. Maintain good water quality with regular water changes and adequate filtration.

Red Flags

  • loss of color or appetite
  • spots or fungus on body or mouth
  • erratic swimming
  • frayed fins

Common Health Issues

Health Issue Symptoms or Causes Suggested Action
Health IssueFin rot Symptoms or CausesFrayed or disintegrating fins; the base of the fins usually reddens. Suggested ActionImprove water quality; consult your aquatic veterinarian for treatment.
Health IssueIch Symptoms or CausesWhite spots appear on fins and body; fish rubs against hard objects or swims awkwardly. Suggested ActionQuarantine fish immediately; use a commercial ich remedy for at least two weeks.


Ask an associate about Petco’s selection of books on Freshwater Livebearers and the variety of Petco Brand products available for the care and happiness of your new pet. All Petco Brand products carry a 100% money-back guarantee.

Because all aquatic life are potential carriers of infectious diseases, such as Salmonella, always wash your hands before and after handling your aquatic life and/or habitat contents to help prevent the potential spread of diseases.

Pregnant women, children under the age of 5 and people with weakened immune systems should contact their physician before purchasing and/or caring for aquatic life and should consider not having aquatic life as a pet.

Go to the Centers for Disease Control at for more information about aquatic life and disease.

This care sheet can cover the needs of other species. See for more information.

Note:The information on this Care Sheet is not a substitute for veterinary care. If you need additional information, please refer to the sources on the following page or contact your veterinarian as appropriate.

Developed with and approved by a qualified veterinarian.