Swordtail
Scientific name: Xiphophorus hellerii
Schooling fish that provides constant movement to tropical community aquariums.
Quick facts
- Approximate size8–12 cm
- Average weight5–10 g
- Life expectancy3–5 years (captivity)
- ActivityDiurnal
Basic information
- Habitat: rivers and streams with moderate current with vegetation in Central America.
- Diet: omnivorous; consumes algae, invertebrates, and prepared food.
- Sexual dimorphism: males with "sword" on caudal fin and gonopodium; females larger and more rounded.
- Predators: larger fish, piscivorous birds, and other vertebrates.
Life in the wild
How this species lives in its natural environment, with the waters, shelters and resources it needs.
Species overview
The swordtail is a classic livebearer and a good example of sexual ornamentation in fish.
Natural habitat
It lives in temperate waters with some current and abundant vegetation.
Behavior
Males compete with each other and actively court females.
Special features
The length of the "sword" can influence female preferences.
Conservation and threats
It is not globally threatened, but introductions outside its range can affect local species.
Curiosities
Striking details about this species that help better understand its biology and role in aquatic ecosystems.
- It is very prolific and can crossbreed with platies in captivity.
- It likes to swim in the middle and upper zone of the aquarium.
- In good conditions it can maintain very vivid colors on the tail and body.
- It has been the subject of studies on sexual selection thanks to the male's "sword".
Welfare profile
Summary of the most critical points if this species is kept in aquariums, ponds or specialized facilities.
Space and facilitiesMedium
It needs aquariums with space to swim and vegetation where to take refuge.
Water quality and parametersMedium
It requires stable and well-filtered water; tolerates a wide range of parameters if they are stable.
Handling and stressLow
It is an active and hardy fish that adapts well to human presence.
Swordtail in captivity
General information aimed at professional facilities, public aquariums and educational projects. It does not intend to promote capture or impulsive keeping of aquatic fauna.
⚠️ Before keeping fish like this species, it is essential to review local regulations, ensure adequate facilities and minimize impact on wild populations.
Suitable facilities
Ideal for community aquariums with calm and similarly sized companions.
Feeding in responsible centers
The diet includes quality dry food, algae, and live or frozen prey.
Handling and welfare
Dense vegetation helps fry survive and reduces stress in adults.
Ethical message
It is important to avoid releases into natural waters, as they can compete with native species.
Many aquatic species suffer from massive captures, uncontrolled trade and irresponsible releases. The priority should always be to protect rivers, lakes and seas, reduce pollution and consume seafood responsibly.