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

Diet: omnivore

pH: 6.5-8

Hardiness: Hardy

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.