Common name: Swordtail
Scientific name: Xiphophorus hellerii
Type of fish: Livebearer
Origin: Central America
Level of difficulty: Beginner
Max size: 4 inches
Growth Rate: Medium
Minimum tank size: 20 gallons
Aggressiveness: Most are peaceful, but some are aggressive
Tankmates: tetras, livebearers, barbs, danios, Corydoras catfishes, dwarf cichlids
Sexing: Males have a distinct "sword" on the ends of their tails. Males also have a gonopodium near their anus.
Notes: Like all livebearers, these fish reproduce easily and quickly. They yield live fry and may even eat their own fry. These fish are naturally green-colored, but after generations of breeding, many color morphs are available. These fish also make great dithers for Central-American cichlids like Firemouths and Convicts.