Description
Xiphophorus hellerii
Swordtails require a tank that is a minimum of 3ft in length, and preferably longer, due to their eventual adult size. More streamlined and agile than platies, swords are often found in fast-flowing habitats and appreciate cooler water and high oxygen levels. They can be kept in community aquariums where no tiny fish are present, and they will appreciate plant cover. They also make excellent companions for smaller species of Central American cichlids such as Thorichthys and Cryptoheros in large aquaria, where they can avoid intruding on spawning territories. Males can become quite competitive towards one another, so it is wise to limit yourself to one male per tank in smaller set-ups. Larger groups are best with three or more males to spread aggression, outnumbered by females. There are numerous colour variants available and the wide selection often mirrors that of platies, due to their ease of hybridisation. Green forms, with or without black speckling, are closest to the wild fish and may be more tolerant of cooler temperatures.
