Aquarium Livestock Pet Care Guides

Guppies, Swordtails, Platies & Other Livebearers


North, Central and South America

Tank Temperature:




Tank Requirements:

Provide plants, driftwood, and other hiding places for fry; will benefit from some aquarium salts (1 tablespoon for every 5 gallons of water).


Omnivorous; will eat shrimp, flakes, small pellets or granules, and meaty frozen foods, such as brine shrimp and bloodworms; feed once daily.


Peaceful; livebearer


Community Safe. Best kept one male with two or more females. An ideal community for variatus can include other variatus, other livebearers (platies, mollies, guppies, swordtails), rasboras, tetras, danios and some catfish from the Corydoras family. To avoid accidental breeding, keep only males or only females. If mixing genders, a ratio of one male to two females is best to avoid males overpowering the females.

Determining Gender

These fish are some of the easiest to determine gender. The anal fin, known as the "gonopodium", is held pointed and tube-like on males while it is open and fan-like on females (as seen in the photo above). Males may show aggression towards each other in the aquarium. Mature male Swordtails also have their trademark long lower lobe of the tail fin but juvenile males may lack this "sword".


Livebearers are fish that give birth to live, free-swimming babies instead of laying eggs and are best-known for their prolific breeding. Livebearers have the ability to deliver several batches of young from a single fertilization from a male. Gestation ranges from 4-6 weeks or 8-10 weeks for larger species. Each batch may number from 25 to more than 100. Most Livebearer parents will eat their babies. To collect or protect the babies, place pregnant females into a breeder net or trap until she delivers, or provide plenty of plants and ornaments where the fry can find safe haven to grow. In a planted tank at least some of the young usually survive.

Species Overview

Common livebearing fish for tropical freshwater aquariums include Swordtails, Platies, Variatus, Mollies, and Guppies. These bright and peaceful little fish come in a variety of colors and patterns and can easily be placed in a tropical community. While these fish share many similarities in behavior and care needs, there are subtle differences that set them apart. Swordtail mature males are easily identified by the elongated lower lobe of their tail fin. Platies and Variatus have a slightly more stocky build than Swordtails. Otherwise they are very similar and may even interbreed. Mollies are even more robust and have the ability to adapt to a wide range of salinity; they can live in pure freshwater or ocean water. Guppies, particularly males, are easily recognized by their huge tails and amazing coloration. Many other livebearer species exist, but they are not as frequently offered for aquariums. 

Keep livebearers in a well-maintained aquarium with live or artificial plants. They prefer a little aquarium salt, though it is not necessary. These fish are peaceful in community tanks. Purchase one male with at least two females of the same species. They will feed on any commercial flake or pellet food, and may also be fed small freeze-dried or frozen foods as treats periodically. They will also eat some algae.

We always suggest that you do further research before adding a new pet to your tank. What we have provided for you are guidelines and suggestions. If you have any further questions or concerns, please contact our fish room at 717-299-5691 ext. 1213 or

Recommended Items

Freshwater Community Food
Plastic Plants
Breeder Nets, Hatcheries & Nurseries