Variatus platy

Water parameters

Tolerated range for this species. Aim for the middle of each band rather than the extremes.

Tank and habitat

Substrate: any.

Behavior

Plant interaction: may nibble soft.

Feeding

Eats anything. Flake, pellets, frozen food, blanched vegetables, algae. Include vegetable matter in the diet; variatus platies graze on algae more actively than southern platies. Feed twice daily in moderate amounts. Color-enhancing foods improve the vibrancy of the many color varieties available. Not competitive or aggressive at feeding time.

Compatibility

• Same family and much the same care as the southern platy (X. maculatus). Variatus platies are slightly hardier and tolerate cooler temperatures (15–25°C), making them suitable for unheated tanks.
• Peaceful, active community fish. Works with everything from tetras and barbs to corydoras and loaches. Males chase females but with less intensity than swordtails.
• Cross-breeds with other Xiphophorus species. Many fish sold as 'platy' in stores are actually variatus-maculatus hybrids. Pure variatus stock is available from specialist breeders.
• Excellent choice for outdoor summer ponds and subtropical setups. The cold tolerance sets them apart from southern platies.

Origin and habitat

Xiphophorus variatus, the variable or variatus platy, is a livebearer native to the Atlantic slope of Mexico, from southern Tamaulipas into northern Veracruz, in warm springs, weedy canals, ditches, and vegetated streams. Meek described it in 1904 as Platypoecilus variatus from the Rio Valles. It is one of the two main platy species in the hobby alongside the southern platy, X. maculatus, and is a touch hardier and more cold-tolerant, comfortable from the mid-teens to mid-twenties Celsius, which makes it a good fish for an unheated tank or a summer pond. Males reach about 5 cm and females up to 7 cm. Wild fish are olive with dark marbling toward the tail, but the trade offers a wide spread of selectively bred colours, sunset, rainbow, blue, gold, red, and high-finned forms among them, and the species hybridises freely with the southern platy and the swordtail, so many trade platies are mixed. It needs moderately hard, alkaline water and does poorly in soft, acidic conditions. It has been introduced and become established almost worldwide through the aquarium trade, and has also served as a genetics research animal.

Breeding

A continuously breeding livebearer. Females carry young for about four to seven weeks and drop broods of roughly twenty to fifty free-swimming fry, sometimes many more in a large female, and store sperm for several broods from one mating. The fry are large enough to take crushed flake and baby brine shrimp at once and grow fast. Notably, it will breed at cooler temperatures than most livebearers, down around 18 to 20 C, which suits unheated tanks and outdoor ponds in the warm months. As with other platies, the adults eat fry in a community tank, so cover or a separate tank is needed to raise many, and the population needs managing to avoid overstocking.

Common problems

There is little to go wrong; this is one of the hardiest aquarium fish, tolerant of temperature swings, a range of water chemistry, and most diets. Farm-raised stock sometimes carries Camallanus worms, seen as red threads at the vent, which need a proper dewormer. The main thing to watch is genetics rather than health: in a mixed tank it crosses readily with southern platies and swordtails, muddling the lines, and fancy colour strains drift back toward wild olive over generations without selective breeding. Keeping pure variatus means keeping it apart from other Xiphophorus.

Bioload

Further reading

• How to cycle a fish tank
• Stocking ideas by tank size