Redtail Catfish

Also known as: Phractocephalus hemioliopterus

The Redtail Catfish is a large, striking freshwater catfish native to South American river systems. The Redtail Catfish originates from Amazon, Orinoco, and Essequibo river basins in South America, including Brazil, Peru, Colombia, Venezuela, and Guyana, reaches Adult size: 100-130 cm in captivity, typically lives 15-20 years, and is kept at 24-28°C (75-82°F). Individual fish vary, so treat this as a general guide rather than a guarantee.

Species at a glance

Origin: Amazon, Orinoco, and Essequibo river basins in South America, including Brazil, Peru, Colombia, Venezuela, and Guyana
Adult size: Adult size: 100-130 cm (39-51 inches)
Life span: 15-20 years
Temperament: Generally peaceful but predatory; may eat smaller fish that fit in its mouth
Tank size: Minimum 1000 liters (264 gallons) for a single adult
Water temp: 24-28°C (75-82°F)
pH range: 6.0-7.5
Diet: Omnivorous scavenger; eats fish, crustaceans, insects, plant matter, and sinking pellets in captivity
Other names: Phractocephalus hemioliopterus

About the Redtail Catfish

The Redtail Catfish is a large, striking freshwater catfish native to South American river systems. It is characterized by its dark body, white ventral surface, and distinctive bright red-orange tail fin. This species can grow over 1 meter in length and requires substantial space to thrive. In the wild, it inhabits slow-moving, turbid waters with soft substrates and abundant cover.

Lifespan and health

With optimal care, Redtail Catfish commonly live 15-20 years in captivity, with some individuals exceeding 25 years in very large, well-maintained systems. Growth is rapid in youth, reaching 30-40 cm (12-16 inches) within the first year under proper feeding and space. Longevity is heavily dependent on tank size, water quality, and diet; cramped conditions or poor nutrition significantly shorten lifespan and increase stress-related disorders. Common health issues include barbel erosion from rough substrates or poor water quality, fungal infections (especially Saprolegnia) following injury, and parasitic infestations like Ichthyophthirius multifiliis (Ich) in stressed individuals. Bloat and swim bladder disorders can occur from overfeeding or low-fiber diets. Monitor for lethargy, loss of appetite, or abnormal swimming, and quarantine new fish for 4-6 weeks. Treatments should use catfish-safe medications, avoiding copper-based products which are toxic to this species.

Overview

Care and tank setup

Tank setup requires a minimum of 1000 liters (264 gallons) with a soft sand or fine gravel substrate to protect its sensitive barbels. Provide ample hiding places using large driftwood, rock caves, and PVC pipes, as this species is nocturnal and prefers dim lighting. Ensure strong filtration capable of turning over the tank volume 4-6 times per hour due to high waste production, and maintain moderate water flow to mimic natural river conditions. Water parameters must be stable: temperature 24-28°C (75-82°F), pH 6.0-7.5, and hardness 2-15 dGH. Perform 30% weekly water changes to control nitrates, which should remain below 20 ppm. Avoid sudden changes in chemistry, as Redtail Catfish are sensitive to stress. Use a secure, weighted lid, as they are powerful and may jump when startled. Feed a varied diet 4-5 times per week for juveniles, reducing to 2-3 times weekly for adults. Offer sinking carnivore pellets, frozen foods (shrimp, krill, bloodworms), and occasional live feeders (guppies or goldfish, quarantined). Supplement with blanched vegetables like zucchini or spinach. Never overfeed; remove uneaten food within 5 minutes to prevent water quality degradation.

Adding a Redtail Catfish? Research the species’ adult size and temperament carefully, quarantine new fish before introducing them to your tank, and buy from reputable aquarium stores or breeders.

Breed information on this page is based on the Wikipedia article on the Redtail Catfish, supplemented with additional research. Reviewed for accuracy.