An exceptionally rare, large-growing 'lower jaw' bichir native to West Africa. Known for its prehistoric appearance and striking dark vertical blotches. While early scientific records logged their size much smaller, modern hobbyist and field consensus acknowledges they can reach nearly 3 feet (75-85cm) in length. They are ambush predators; while peaceful to large tankmates, they will consume any fish that fits in their surprisingly large mouths.
Guinean Bichir At a Glance
Guinean Bichir Tank Requirements
Will Guinean Bichir fit in your tank?
Care guides tell you what Guinean Bichir needs, the next question is whether your tank can safely provide it. Test Guinean Bichir against your tank size, maintenance needs, and the fish you already keep before you buy.
Useful setup supplies
We may earn from qualifying purchases
Guinean Bichir Water Parameters
Water care products
We may earn from qualifying purchases
Guinean Bichir Temperament & Compatibility
Guinean Bichir Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Adult (Standard)
Fully grown adult. Requires a massive aquarium (150+ gallons minimum, preferably 180+ for a 6-foot footprint) and heavy filtration to handle its high-protein, carnivorous diet. Must only be kept with very robust tankmates like large cichlids, Datnoides, or other large Bichirs.
Same care requirements as the base species
Also known as: Monster Fish, Large Bichir
Juvenile (Grow-out)
Young specimens commonly sold in the trade. While they can temporarily live in smaller tanks, they possess a fast growth rate initially and require a high-protein diet (bloodworms, chopped shrimp, pellets). They will rapidly outgrow standard aquariums.
Differs in 4 traits from base species
Also known as: Baby Bichir, Growout
Guinean Bichir Care Guide Summary
The Guinean Bichir, scientifically known as Polypterus ansorgii, 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 semi-aggressive, this species primarily occupies the bottom zone of the aquarium and produces a extreme level of biological waste.
To thrive, the Guinean Bichir requires a freshwater only aquarium with a minimum volume of 680 litres and a tank length of at least 180 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 6.5–7.5 and a general hardness of 5–15 dGH. A low water flow is preferred.
Due to its specialist needs, the Guinean 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.
Guinean Bichir Habitat Setup
When setting up an aquarium for the Guinean Bichir, a low 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, driftwood, which can serve as both a hiding place and a dietary supplement, and floating plants to diffuse overhead light and create shaded areas. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.
Guinean Bichir Compatibility Notes
Classified as semi-aggressive, the Guinean 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. Selecting tankmates that favour different water layers from the bottom zone can help reduce competition and territorial overlap.
Guinean Bichir Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Guinean Bichir.
Guinean Bichir Feeding & Diet Considerations
The Guinean Bichir is a predatory species that will readily consume small fish, so nano or bite-sized tankmates should be avoided and is primarily active at dusk and dawn, so offering food shortly after lights-off ensures it receives adequate nutrition.
Feeding products
We may earn from qualifying purchases
.webp?2026-04-25T14%3A35%3A38.022Z)
Frequently Asked Questions About Guinean Bichir
How big does Guinean Bichir get?
Guinean Bichir (Polypterus ansorgii) 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 Guinean Bichir need?
A minimum aquarium volume of 680 litres and a tank length of at least 180 cm are recommended for Guinean Bichir. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Guinean Bichir need?
Guinean Bichir thrives in freshwater only conditions with a temperature range of 24–28°C, a pH between 6.5 and 7.5, and a general hardness of 5–15 dGH. A low water flow is preferred.
Is Guinean Bichir peaceful or aggressive?
Guinean Bichir is classified as semi-aggressive with an aggression score of 5 out of 10. They can work in community setups but may clash with certain tankmates.
Can Guinean Bichir live alone?
Yes, Guinean Bichir can be kept singly or in a group. They are flexible and adapt well to both setups.
Does Guinean Bichir have any special tank requirements?
Yes. Guinean Bichir benefits from sand (sifters), smooth gravel (sensitive barbels), driftwood (digestion/hiding), and plants - floating in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Does Guinean Bichir need a lid on the tank?
Yes. Guinean 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.
Plants That Suit Guinean Bichir
These plants pair well with Guinean Bichir based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
Amazon Frogbit
Limnobium laevigatum
Asian Watergrass
Hygroryza aristata
Asian Watermoss
Salvinia cucullata
Carolina Mosquito Fern
Azolla caroliniana
Common Duckweed
Lemna minor
Crystalwort
Riccia fluitans
Fish Similar to Guinean Bichir
Mokele-mbembe Bichir
Polypterus mokelembembe
A fascinating 'living fossil' from the Congo River Basin, named after a mythological African dinosaur. While considered one of the smaller bichir species, it still reaches up to 36cm (14 inches). Like all bichirs, they possess a modified swim bladder acting as a lung, requiring access to atmospheric air. They are nocturnal ambush predators with heavily armored, eel-like bodies.
Congo Bichir
Polypterus endlicheri congicus
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.
Marbled Bichir
Polypterus polli
An ancient, prehistoric-looking 'upper-jaw' bichir native to the Congo River basin. They are fascinating bottom-dwelling predators with paired lungs, requiring access to the water's surface to breathe atmospheric air. While generally peaceful towards tank mates too large to swallow, they are highly opportunistic nocturnal predators. A tight-fitting lid is mandatory, and fine sand substrate is critical to prevent fatal impaction during their lunging feeding behavior.
Palmas Bichir
Polypterus palmas palmas
An ancient, primitive bottom-dweller from West Africa known for its dinosaur-like appearance and ability to breathe atmospheric air using modified lungs. While it is one of the smaller 'upper jaw' Bichir species, it is a highly capable ambush predator. It is generally peaceful towards fish too large to swallow, but completely unsafe for small community fish. A tight-fitting lid is absolutely mandatory to prevent escaping.
Polypterus Bichir Lapradei
Polypterus bichir lapradei
The Lapradei Bichir is a massive, ancient, air-breathing predatory fish native to West Africa. Featuring distinct dorsal finlets and a heavily armored, snake-like body, it is a fascinating 'monster fish'. As nocturnal ambush predators, they will consume any tank mate that fits in their surprisingly large mouths. However, they are remarkably peaceful with robust companions that are too large to eat. A tight-fitting lid is absolutely mandatory as they are notorious escape artists.
Delhezi Bichir (Armored Bichir)
Polypterus delhezi
An ancient, air-breathing predatory fish from the Congo River basin. Known for its distinct black vertical bands and dinosaur-like dorsal finlets. They are bottom-dwelling ambush predators with poor eyesight but an excellent sense of smell. While generally peaceful with similarly sized or larger fish, they are opportunistic piscivores and will eat anything that fits into their surprisingly large mouths.