Congo bichir

Care at a glance

Overview

The Congo bichir is the giant of the family, a meter-class predator that only suits huge, custom aquariums or indoor ponds, so this is a monster-tank commitment measured in many hundreds of liters, at least 1,000 and realistically far more. It is a slow, nocturnal ambusher that is mostly peaceful but will swallow any fish that fits in its mouth, so keep it alone or with equally large, robust tankmates. Feed meaty foods such as whole prawn, mussel, earthworms and large sinking carnivore items in the evening. It needs a soft sand floor to protect its belly and a heavy, tight lid, since even big bichirs climb.

In the wild

It patrols the floors of large rivers, channels and floodplains across the Congo basin in central Africa, in warm, soft to neutral water. Recreate that on a grand scale with a sand bottom, big driftwood and open swimming and resting room, with gentle to moderate flow. Keep it warm at 24 to 28 C and from slightly acidic to slightly alkaline, about pH 6.2 to 7.8. Bichirs cope with low oxygen well because they can breathe air.

Good to know

Polypterus congicus is the largest bichir in the family Polypteridae, reaching about 97 cm, its brownish-grey body crossed by around eight irregular dark bars. It is a heavy, slow-growing predator sheathed in the hard, interlocking scales typical of the family. Its breeding is not recorded in home aquaria, which is no surprise given the space a full-grown fish would need.

Did you know

It breathes air to survive. Like all bichirs, the Congo bichir has a pair of simple lungs and rises to gulp at the surface, which lets it endure stagnant, oxygen-poor water and even short spells out of water if it stays damp.

Common questions

Related species

• 

  Nile bichir

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  27.6 in (70 cm)185 gal (700 L)77–84°F (25–29°C)

• 

  Saddled bichir

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  25.6 in (65 cm)151 gal (570 L)77–84°F (25–29°C)

• 

  Ornate bichir

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• 

  Weeks' bichir

  Polypterus weeksii

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• Teugels' bichir

  Polypterus teugelsi

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• Ansorge's bichir

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  15.7 in (40 cm)119 gal (450 L)75–82°F (24–28°C)