Green Swordtail

Xiphophorus hellerii

Animalia›Chordata›Actinopterygii

Variety of Swordtail · green

📍 Central America

The natural wild-type coloration of the swordtail, featuring an olive-green to brown body with a faint lateral stripe and the characteristic elongated lower caudal fin lobe in males. It is the closest in appearance to the wild fish and is hardy and active, suitable for community tanks with hard, alkaline water.

Size4.5"

Min Tank20g

School3+

peaceful

Zonemid

Care Guide

Diet

Green swordtails are omnivorous and should be fed high-quality flake food or small pellets as a staple, supplemented 2-3 times weekly with frozen foods like brine shrimp, daphnia, or bloodworms. Include vegetable matter such as blanched spinach or algae wafers to support digestive health. Feed small amounts once daily, only what they can consume in 2-3 minutes.

Behavior

Active and peaceful swimmers that spend most of their time in the mid-water column, though they will explore all tank levels. Males are territorial toward each other and may display aggressive fin-spreading, so only one male per tank is recommended unless the tank is very large. They are social with females and other peaceful community fish, displaying characteristic darting movements and occasional surface feeding.

Breeding

Swordtails are prolific livebearers that breed readily in captivity with minimal intervention; females can produce 20-100 fry every 4-6 weeks once mature. Provide dense vegetation or breeding box to protect fry from predation by adults. Separate males and females if population control is desired, as uncontrolled breeding will quickly overpopulate the tank.

Tank Mates

Guppy

Similar peaceful temperament and water requirements; males may compete for territory but generally coexist well

good

Platy

Closely related livebearers with identical care needs and compatible social behavior

excellent

Neon Tetra

Small schooling fish that occupy mid-water and pose no threat; swordtails ignore them

good

Bristlenose Pleco

Peaceful algae eater that stays small and occupies bottom zone without competing for resources

excellent

Ramshorn Snail

Peaceful invertebrate that helps control algae and does not compete with fish for food

good

Common Diseases

Fin Rot

Symptoms

Frayed, torn, or disintegrating fins; white or dark edges on fin tissue; lethargy

Treatment

Perform 25-30% water changes every 2-3 days, improve water quality, maintain temperature at 76-78°F, and treat with aquarium salt (1 teaspoon per 5 gallons) or antibacterial medication if severe

Ich (Ichthyophthirius multifiliis)

Symptoms

White spots resembling salt grains on body and fins; scratching against objects; rapid breathing

Treatment

Raise temperature gradually to 82-86°F over 48 hours, perform daily 25% water changes, and treat with ich medication or aquarium salt following product instructions for 7-10 days

Velvet Disease

Symptoms

Fine golden or rust-colored dust on body; lethargy; rapid gill movement; loss of appetite

Treatment

Reduce light exposure, raise temperature to 80-82°F, perform 25% water changes daily, and treat with copper-based medication or methylene blue following dosage instructions

Dropsy

Symptoms

Swollen abdomen; scales standing out like a pinecone; lethargy; loss of appetite

Treatment

Isolate affected fish, perform frequent water changes, maintain optimal water quality, and treat with antibacterial medication; prognosis is often poor if advanced