Red-Tail Catfish

Phractocephalus hemioliopterus

Catfish

A massive, fast-growing predatory catfish from the Amazon basin. Famous for its voracious appetite, bulldozer-like behavior, and distinct red caudal fin. Due to its enormous adult size (often exceeding 4 feet), it is strictly a 'monster fish' that requires a heated indoor pond or a colossal custom aquarium. It is highly predatory and will swallow absolutely any tank mate that can fit into its cavernous mouth.

At a Glance

Adult Size120 cm
Body ShapeDepressed
Growth RateFast
TemperamentAggressive
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputExtreme
StockingSolo or group

Tank Requirements

Minimum Volume3800 L
Minimum Length300 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Sand (Sifters)Smooth Gravel (Sensitive Barbels)Driftwood (Digestion/Hiding)

Water Parameters

Temperature2028°C
pH67.5
Hardness315 dGH

Temperament & Compatibility

Aggression LevelAggressive
7/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least1 (solo is fine)
Max per TankNo limit
Can Live Alone?Yes
Behavior Traits
Piscivore (Eats small/nano fish)Plant DestroyerDigger (Disturbs Substrate)Nocturnal

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard (Adult)

The fully grown adult Red-Tail Catfish. Requires heavy-duty filtration, bare-bottom or sand substrate, and a tank or pond measured in thousands of liters.

Same care requirements as the base species

Also known as: Adult, Monster, Full Grown

Juvenile (Grow-out)

Juveniles are commonly sold at 5-10cm. They grow at an astonishing rate (often up to an inch per month initially) and possess an incredibly fast metabolism. They must only be purchased if a pond or custom tank upgrade is already planned.

Differs in 5 traits from base species

Also known as: Baby, Juvenile, RTC Baby

Adult Size10 cm
TemperamentSemi-Aggressive
Min Volume200 L
Min Length90 cm
Growth RateFast

Red-Tail Catfish Care Summary

The Red-Tail Catfish, scientifically known as Phractocephalus hemioliopterus, belongs to the Catfish family group. Adults reach a maximum size of approximately 120 cm and have a depressed body shape with a fast growth rate. Classified as aggressive, this species primarily occupies the bottom zone of the aquarium and produces a extreme level of biological waste.

To thrive, the Red-Tail Catfish requires a freshwater only aquarium with a minimum volume of 3800 litres and a tank length of at least 300 cm. Water temperature should be maintained between 20°C and 28°C, with a pH range of 67.5 and a general hardness of 315 dGH. A moderate water flow is preferred. To replicate their natural habitat, the tank should include sand (sifters), smooth gravel (sensitive barbels), and driftwood (digestion/hiding).

Red-Tail Catfish can be kept singly or in a group, making them flexible additions to most setups. Keepers should be aware that this species will prey on fish small enough to fit in its mouth, may uproot or eat live plants, and is primarily active at night or during twilight hours. This species is available in 2 varieties: Standard (Adult) and Juvenile (Grow-out). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.


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