Congo Bichir

Polypterus endlicheri congicus

Oddballs
Reviewed by Guidarium Editorial DeskUpdated May 3, 2026

The Congo Bichir is a prehistoric-looking, bottom-dwelling monster fish and one of the largest species in the Polypteridae family. They are obligate air-breathers and ambush predators that will eagerly consume any tankmate small enough to fit in their surprisingly large mouths. Due to their massive adult size, they require extremely large custom aquariums, heavy filtration, and a tight-fitting lid to prevent escapes.

Congo Bichir At a Glance

Adult Size75 cm
Body ShapeEel
Growth RateModerate
TemperamentAggressive
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputExtreme
StockingSolo or group

Congo Bichir Tank Requirements

Minimum Volume800 L
Minimum Length200 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Sand (Sifters)Smooth Gravel (Sensitive Barbels)Driftwood (Digestion/Hiding)
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Will Congo Bichir fit in your tank?

Care guides tell you what Congo Bichir needs, the next question is whether your tank can safely provide it. Test Congo Bichir against your tank size, maintenance needs, and the fish you already keep before you buy.

Congo Bichir
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Congo Bichir Water Parameters

Temperature2430°C
pH6.58
Hardness520 dGH

Congo Bichir 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)Shrimp EaterNocturnalJumper (Lid Required)

Congo Bichir Varieties

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

Adult (Standard)

Fully grown Congo Bichir. Demands a massive footprint (minimum 6.5ft/200cm length) and heavy filtration to handle its extreme bioload. Tankmates must be high-bodied and large enough to avoid becoming a meal.

Same care requirements as the base species

Also known as: Full Grown, Adult Bichir

Juvenile (Grow-out)

Young Congo Bichir. While they can be temporarily housed in smaller aquariums, they grow incredibly fast and will quickly require a massive tank upgrade. Will eat smaller tankmates.

Differs in 4 traits from base species

Also known as: Baby Bichir, Juvenile Congo

Adult Size15 cm
Min Volume200 L
Min Length120 cm
Growth RateFast

Congo Bichir Care Guide Summary

The Congo Bichir, scientifically known as Polypterus endlicheri congicus, belongs to the Oddballs family group. Adults reach a maximum size of approximately 75 cm and have a eel body shape with a moderate 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 Congo Bichir requires a freshwater only aquarium with a minimum volume of 800 litres and a tank length of at least 200 cm. Water temperature should be maintained between 24°C and 30°C, with a pH range of 6.58 and a general hardness of 520 dGH. A moderate water flow is preferred.

Due to its specialist needs, the Congo Bichir is best suited for fishkeepers who can provide a carefully planned setup. This species is available in 2 varieties: Adult (Standard) 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.

Congo Bichir Habitat Setup

When setting up an aquarium for the Congo Bichir, a moderate water flow best suits their natural preferences. Because this species occupies the bottom zone, the aquarium layout should prioritise sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour, smooth gravel or rounded substrate to protect their sensitive barbels, and driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.

Congo Bichir Compatibility Notes

Classified as aggressive, the Congo Bichir is adaptable and can be kept singly or in a small group, offering flexibility when planning a community tank. When choosing tankmates, any fish small enough to fit in its mouth will likely be eaten and ornamental shrimp are not safe companions. Selecting tankmates that favour different water layers from the bottom zone can help reduce competition and territorial overlap.

Who Congo Bichir Is Actually For

Congo Bichir is best for a fishkeeper who expects a species with attitude and plans the tank around that behavior and can provide someone who understands its individual space requirements. It makes the most sense for a hobbyist who will actually build around its needs, especially sand.

The most common mistake is treating Congo Bichir like any other community fish and skipping the soft sand it needs to forage safely. Another frequent problem is forcing it into an over-busy community when it would do better with more room or more deliberate tankmate choices.

Congo Bichir Feeding & Diet Considerations

The Congo Bichir is a predatory species that will readily consume small fish, so nano or bite-sized tankmates should be avoided, will hunt and eat ornamental shrimp, making it unsuitable for shrimp-focused setups, and is primarily active at dusk and dawn, so offering food shortly after lights-off ensures it receives adequate nutrition.

Frequently Asked Questions About Congo Bichir

How big does Congo Bichir get?

Congo Bichir (Polypterus endlicheri congicus) typically reaches a maximum adult size of approximately 75 cm. They have a eel body shape and a moderate growth rate.

What tank size does Congo Bichir need?

A minimum aquarium volume of 800 litres and a tank length of at least 200 cm are recommended for Congo Bichir. This ensures enough swimming space and helps maintain stable water conditions.

What water parameters does Congo Bichir need?

Congo Bichir thrives in freshwater only conditions with a temperature range of 24–30°C, a pH between 6.5 and 8, and a general hardness of 5–20 dGH. A moderate water flow is preferred.

Is Congo Bichir peaceful or aggressive?

Congo Bichir is classified as aggressive with an aggression score of 7 out of 10. Careful tankmate selection is essential to avoid conflict.

Can Congo Bichir live alone?

Yes, Congo Bichir can be kept singly or in a group. They are flexible and adapt well to both setups.

Is Congo Bichir safe with shrimp?

No. Congo Bichir is known to eat ornamental shrimp and is not recommended for shrimp tanks. Even larger shrimp species like Amano Shrimp may be at risk.

Does Congo Bichir have any special tank requirements?

Yes. Congo Bichir benefits from sand (sifters), smooth gravel (sensitive barbels), and driftwood (digestion/hiding) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Does Congo Bichir need a lid on the tank?

Yes. Congo Bichir is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
May 3, 2026
Last updated
May 3, 2026
Issues or corrections?
Contact the editorial team

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