Like their name suggests, Livebearers –including Guppies, Mollies, Platys and Swordtails – give birth to live young. Find out more about this exciting variety of community fish.


Members of the Poeciliidae family are widely distributed from the Southern United States through Mexico and Central America to South America. This group of freshwater fish includes aquarium favourites such as Mollies, Guppies and Platys – all Livebearers.


Guppies originate from South America and the West Indies. Mollies are native from Mexico to Venezuela. Platys and Swordtails are native from Mexico to Guatemala.

Scientific names

Popular Livebearers kept in aquariums include Guppies (Poecilia Reticulata), Mollies (Poecilia Latipinna, P. Velifera), Platys (Xiphophorus Maculatus, X. Variatus) and Swordtails (Xiphophorus Helleri). These species belong to the Livebearing Tooth Carp Family or Poeciliidae.

Maximum size and longevity

Depending on the species, sizes can range from three to 13cm.

Water parameters and care

Livebearers generally require harder water with pH over neutral.
Temperature: 22 to 27°C
pH: 6.5 to 7. 8
Ammonia: low to 0ppm
Nitrite: low to 0ppm
Nitrate: under 20ppm
General Hardness (GH): 100 to 300ppm


Almost all of the Livebearers mentioned are top feeders and will readily take most artificial and frozen foods. However, they should be given a diet with high vegetable content and a dry food should be used occasionally. Fry (babies) are about seven to 10mm in length when born and are probably the most easily raised species as they will feed off finely ground dry foods and do not require smaller live foods, like most other species when beginning to feed.


Livebearers are compatible with most community species in a densely planted community tank. Mollies prefer slightly alkaline water and will do best with a little sea salt added to the aquarium. Fully grown Swordtails may get a little aggressive with small peaceful species such as Neon Tetras, but in a well-planted tank should pose no problems. Find out more about each specific species at Petbarn’s Petspot.

Colour and varieties

While there are many beautiful wild forms of Livebearers, these species have been selectively bred throughout the world to produce a huge variety of colours, body shape and fin arrangement.

General information

Guppies are probably the most popular Livebearer among both aquarium owners and advanced breeders. The once humble, dull-coloured Guppy has become a sought-after fish for pet parents who are interested in a range of colours and finnage. Their ease of breeding means that it is the first species many hobbyists begin to breed. However, because of intense breeding, fancier Guppies can be harder to maintain.
Platys and Swordtails are of the same genus and are very similar in some aspects. In fact, interbreeding between the two species is possible. (The main difference is that male Swordtails have a ‘sword’ on their caudal tails.) These two groups of fish are also popular, very colourful and active. They are robust and tolerant of a wide range of aquarium conditions and are recommended for beginners. Mollies also make a great addition to the community aquarium and come in a range of bright colours and varieties.

Why they make great pets

Livebearers make great pets and are very popular because they are able to thrive in a variety of water conditions and they do very well in planted aquariums. They live relatively long lives, which means you may get to witness the birth of several generations of fry. Livebearers are great beginner fish and provide a fantastic learning experience for both children and adults. Though peaceful in temperament, it is a good idea to keep several pairs of the same species in a tank to eliminate any potential aggression.


Water changes can be done as necessary but you should aim to change at least 10 to 20 per cent weekly to keep the fish healthy and tank environment free of organic build-up.

Your friendly Petbarn team member will be able to answer all of your fish health questions. Head in-store for great products, information and advice to help keep your fish in perfect condition.

If you have decided to create a tank for Livebearers, don’t miss our video on setting up the aquarium: