TankBud

Sheepshead swordtail

Xiphophorus birchmanni

Also known as Birchmann's swordtail, Swordless swordtail

FreshwaterFish

Sheepshead swordtail (Xiphophorus birchmanni)
Dnoerholm · CC BY-SA 4.0

Care at a glance

Temperature
68–81°F
20–27°C
pH
7.2–8.2
Adult size
2.8 in
7 cm
Minimum tank
24 gal
90 L
Temperament
Mostly peaceful
Social behavior
Social
Swim level
Middle
Diet
Omnivore
Difficulty
Medium
Breeding
Livebearer · Medium
Rarity
Rare
Family
Poeciliidae
Origin
Native to the Rio Panuco basin in Hidalgo, Mexico, in fast flowing, well oxygenated streams.

Overview

The sheepshead swordtail is a stream fish for a long, cool tank with real flow. It is best kept by someone with a little experience.

Did you know

Female sheepshead swordtails can be swayed by the scent of related species. That is one reason natural hybrids with Xiphophorus malinche form where their streams meet. These natural hybrid zones are heavily studied by geneticists.

Caring for the sheepshead swordtail

Sheepshead swordtails are mostly peaceful but active. Keep a group with several females per male, in a longer tank of 24 gal (90 L) or larger. Give them current and open swimming room.

They want cooler, well-oxygenated water with brisk flow, not warm, still water. Keep it medium hard to hard, at 68 to 81°F (20 to 27°C) and a pH of 7.2 to 8.2. Feed a varied diet with plenty of vegetable matter, plus frozen daphnia, brine shrimp and bloodworm.

Males have a tall dorsal fin and a blunt, high-headed profile, and they court females with that fin and their body barring. Females give birth to 20 to 40 live young, and breeding them is of medium difficulty.

Good to know

The sheepshead swordtail, Xiphophorus birchmanni, is a swordless swordtail. Despite the name, males grow no sword. Both sexes are silvery with dark vertical bars.

In the wild

The sheepshead swordtail is native to the Rio Panuco basin in Hidalgo, Mexico. It lives in fast-flowing, well-oxygenated mountain streams.

Weekly picks

Tank mates

The sheepshead swordtail is a mostly peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a sheepshead swordtail need?

A sheepshead swordtail needs at least 24 gal (90 L). It spends most of its time in the middle.

What temperature and pH does a sheepshead swordtail need?

A sheepshead swordtail is comfortable at 68–81°F (20–27°C) with a pH of 7.2–8.2.

What does a sheepshead swordtail eat?

A sheepshead swordtail eats a varied diet with plenty of vegetable matter. Add frozen daphnia, brine shrimp and bloodworm.

How big does a sheepshead swordtail get?

An adult sheepshead swordtail reaches about 2.8 in (7 cm).

How can you tell a male sheepshead swordtail from a female?

Males have a tall dorsal fin and a blunt, high-headed profile.

How does a sheepshead swordtail breed?

A sheepshead swordtail female gives birth to 20 to 40 live young. Males court the females with their large dorsal fin and body barring, and breeding them is of medium difficulty.

Related species