Variable Platy

The variable platy belongs to the Poeciliidae, the family of livebearing toothcarps. Described in 1904 as Platypoecilus variatus, it is a longer, larger fish than the common platy: females reach about 7 cm, while males stay smaller and carry a gonopodium, the anal fin modified into a copulatory organ. Wild fish show an olive to bluish back and a yellow-orange tail, but decades of selection have produced the red, tiger and sunburst strains that fill the trade. The species is native to the Atlantic slope of north-eastern Mexico, in southern Tamaulipas and northern Veracruz, where it lives in the slow, warm water of vegetated canals, ditches and springs. These hard, alkaline habitats explain its taste for neutral to basic, well-mineralised water. Introduced populations are now established in several other countries. Hardy and peaceful, it is an excellent community fish for beginners. Keep a group of at least five, with two females per male so that no single female is harassed, in 80 litres or more. It is omnivorous and takes flake, frozen food and plant matter; algae or blanched vegetables suit it well. Breeding is the real pitfall: females give birth after four to seven weeks, broods of over a hundred fry are not unusual, and an unmanaged population quickly outgrows the tank.