About the Platy
Species Type: Freshwater Fish
Care Level: Very Easy. Will tolerate a wide range of water parameters including pH, temperature and hardness. Can tolerate higher nitrate levels than other fish and is hardy enough to withstand the cycling process. Will readily eat prepared foods and has no special care requirements.
Origin: North and Central America: from Veracruz, Mexico down to Belize. Inhabits creeks and swamps, warm springs, canals and ditches. Typically slow-moving water, with aquatic and marginal vegetation. The species is now found in several of the US states and was introduced in Hawaii.
Compatibility/Temperament: Very peaceful, much moreso that its close relative the swordtail and molly. Should not be kept with other livebearers, especially Xiphophorus hellerii (swordtail), X. variatus (another platy species) and the guppy, as it will likely interbreed. Suitable tankmates include similar-sized non-aggressive fish that prefer basic hard water. Males may be housed without females; if females are included, there should be several females for each male to avoid stress from the attentions of males.
The subject species is referred to as the Common or Southern Platy in order to distinguish it from Xiphophorus variatus, another distinct species of Platy. The original wild form of this fish is a plain grayish brown to olive color, showing a slight sparkle with "salt and pepper" markings scattered over the body. Through selective and cross-breeding, there are now many forms including the Sunset, Moon, Red Wagtail, Tuxedo, Bumblebee, Mickey Mouse, and hifin; the range of colors and fin shapes is almost unlimited.
The male's anal fin is modified into a gonopodium by which he transfers sperm into the female. This is the most reliable means of determining the sex of the fish; as mentioned under temperament, if both sexes are to be housed in the same aquarium, there should be more females than males to provide some rest for the females from the attention of the males. Maintaining males and females in the same tank will result in regular batches of fry, and once impregnated, a female can deliver several successive batches every 4-6 weeks on her own [this is known as superfetation]. In fry, this impregnation can occur before the males attain their colouration, so fish must be separated out very early if the aquarist wishes to selectively breed them.
No particular effort is needed to breed them and eventually rearing the fry as the fry themselves are well developed enough to eat finely-ground prepared foods and brine shrimp nauplii. Fry can number up to 70 each time, although 20-50 is more usual, and require hiding places such as thick floating plant cover or they will be readily eaten by the adults. All breeder traps are best avoided as they have the tendency to stress the females. Fry become sexually mature by 2-3 months depending on the conditions provided to them.
The aquarium should be well planted and have a minimal flow from the filter. The substrate may be sand or fine gravel, with river rock and/or bogwood. This fish prefers to swim in the middle level of the aquarium. It has a life span of about three to three and a half years.
This species was described by A. Gunther in 1866 as Platypoecilus maculatus. The common name of "Platy" comes from this original scientific name. Rosen & Bailey (1963) transferred the species into the genus Xiphophorus which presently holds 26 described species. The genus name is derived from the Greek xipho [=sword] and phorus [=bearer], a reference to the genus type species X. hellerii (swordtail). The species epithet is the Latin for "having been spotted."
Rosen, D.E. and R.M. Bailey (1963), "The poeciliid fishes (Cyprinodontiformes), their structure, zoogeography, and systematics," Bulletin of the American Museum of Natural History, volume 126 (art. 1), pp. 1-176.
Omnivorous by nature, feeding on insects, worms, crustaceans and plant matter. Accepts all prepared foods, a portion of which should be algae/kelp/spirulina-based. Blanched spinach, yam, zucchini may be offered. Frozen or live bloodworms, daphnia, shrimp, insects.
Males attain 5 cm (2 inches), females 8 cm (3 inches).
Minimum Tank Suggestion
Ideal water parameters for Platy
Medium hard to hard (9-30 dGH), basic (pH 7 to 8), temperature 20-28C/68-82F. Better at temperatures in the lower to middle part of the given range. This species like all livebearers will not last in soft, acidic water.