Back to top

The Platy – Southern, Variable and Swordtail Platies


Rainbow Platy

The Platy is probably one of the easiest of livebearers to keep and to breed.

The Platy is a peaceful livebearing tropical fish which graces any aquarium, is easy to look after and is relatively easy to breed so is ideal for beginner and seasoned aquarists alike.

Origins of the Platy

There are three original subspecies within the Platy family as follows:

  • The Southern (or Common) Platy (Xiphophorus Maculatus)
  • The Variable Platy and (Xiphophorus Variatus)
  • The Swordtail (or Spiketail) Platy (Xiphophorus Xiphidium)

The Southern Platy is found in the wild in the freshwaters of Mexico, Guatemala, Belize and Nicaragua.

The Variable Platy is found on the Atlantic slope of Mexico – particularly in the waters of Rio Cazones and Rio Panuco.

The Swordtail Platy is found only in the waters of Rio Soto La Marina in Mexico, is somewhat rare and difficult to find via a local stockist.

Some of the species are hybrids, due to cross-breeding with Swordtails, a significantly larger livebearer with a distinctive sword on the lower part of the male caudal fin.

Characteristics of the Platy

An adult female Platy will grow to up to three inches in length whilst the smaller male Platy will only reach around two-and-a-half inches in length. The Platy is an ideal aquarium fish, as it is a very peaceful fish both as a single species and with other species.

You will see from the location of its mouth that it is a top-feeder.

As is common amongst livebearers, the male fish has the adapted anal fin (the gonopodium) for mating with the female whilst (again, typical amongst livebearers) the female has a significantly larger body.

Due to hybridization, many fishes purporting to be Platies are likely to be a mix of Swordtail and Platy though this may not become apparent in younger fishes, as the caudal fin only develops as the fish grows. The hybrid males generally have far shorter “swords” than the purebred Swordtail Platy or Swordtail and it seems far easier to purchase a hybrid than a purebred Swordtail Platy as this latter is hard to come by, being that it is a comparatively rare fish.

The male Platy can grow to around 2.5″ whilst the female Platy can grow to around 3″. The adult Platy in the wild enjoys gently flowing waters. Due to the small size of the adult Platy, a tank of only 24″ in length is recommended as a minimum size.

Feeding the Platy

Being omnivorous but with a vegetarian bias, the Platies will accept flaked food, daphnia, bloodworm, tubifex worms as well as brine shrimp and, as always, it is better to provide sufficient food for your fishes to consume in two to three minutes once per day.

Platies, being mainly vegetarian, will browse off your plants therefore, if this browsing becomes detrimental to your plants then you may wish to feed them twice daily. Some aquarists feed their Platies three times daily but this would be unusual.

The Platy – Video

Breeding the Platy

A typical brood of Platy can number up to 80 fry and of these, around 70% are likely to be female. This is quite typical amongst livebearers and is also an indication that for each male Platy you should have at least three female Platies, preferably four in my experience.

As with all livebearers, the male Platy is ever-eager to mate so having three or four females for each male gives the females some respite from the constant attentions of the male.

Platies are known for their tendency to jump out of the water in the aquarium so it is advised that you have a cover over your aquarium (with holes for feeding and ventilation). I learned this to my cost as a novice aquarist when one of my Wagtail Platies jumped clear of the aquarium and onto the floor.

The female is also able to store the sperm packages from males for several months so, in the absence of males, the female can use that stored sperm to fertilize batches of eggs. The female can also simultaneously bear the young of different males (polyandry).

The breeding cycle is around 30 days so you can anticipate the addition of up to 80 fry around twelve times per year.

The Platy will eat its own young so ensure wither that you employ a breeding trap to protect the fry of that there is plenty of cover in which the fry can escape the predation on the adults (and other fishes in the aquarium.

The Platy and Swordtail will interbreed so if you wish to ensure that you maintain your stock in the pure form them it is advised that the two species are not kept in the same tank.

Male Platies, whilst in breeding mode, can become aggressive particularly towards their intended mate.

Interaction with other species

In the wild, Platies are not shoaling fishes but are generally good community fishes in the aquarium and will happily coexist in small groups.

Larger or aggressive fishes (such as some Cichlids) have been known to target Platies. Two such culprits cited are the Convict Cichlid and the Jack Dempsey Cichlid but mixing Platies with Cichlids, in general, is not recommended.

As stated in the section on breeding, Platies will interbreed with Swordtails so it is advised that unless you are content for them to interbreed then don’t include Platies of either sex in the same aquarium as Swordtails.

Susceptibilities of the species

The Platy, like most livebearers, is a hardy species so is likely not to be susceptible to disease or to predation (excepting from certain Cichlids).

As with all fishes, always keep a close eye out for White Spot (“Ich” or “Ick”) and fin rot as well as flukes.

Varieties of Platy

The Southern Platy has been kept in aquaria since the very early 20th century and the Variable Platy since the 1930s so, bearing in mind their short (monthly) breeding cycle together with hybridization with Swordtails, there are now many variations of Platy available from stockists, most of which seem to be favoured above the less colourful Platy found in the wild. Such variations include:

  • 24 Karat Gold Platy
  • Blue Platy
  • Lemon Platy
  • Mickey Mouse Platy
  • Orange Platy
  • Rainbow Platy
  • Red Platy
  • Wagtail Platy
  • White Platy
  • Yellow Platy

Featured image courtesy of: Takira2

Mike Wheeler

I started keeping freshwater tropical fish in 1972 and it has been something of a passion ever since. In this website, my aim is to build up an everyman's guide to help the everyday aquarist get the best from this inspiring and entertaining hobby.

Recent Posts