Bichir fishes

Not every fancier of tank fishes has met bichir fish. Though, those who have will never be able to forget this unique and extraordinary fish, no wonder that its second name is dragon bichir. In this article you will read about care, feeding and how to choose its tank mates. Unfortunately, it is quite complicated to describe each genus of the fish separately, but in general they have almost the same requirements as for care and keeping in a tank.

Only the fish size imposes some restrictions. Because some species are unsuitable to keep in a home aquarium due to their large size.

Habitat in the wild

Bichirs (lat. Polypteridae) is a family of freshwater ray-finned fishes, the only one in the order Polypteriformes and subclass Cladistia. Nowadays, there are 14 modern genus of the fish known and spread over tropical Africa.

Another fish E. calabaricus also belongs to this class. Aquarists know it as a reedfish or ropefish. This is quite an ancient group that has some similar characters with lobe-finned fishes and lungfishes that appeared independently. The earliest fossil remains of polypterids fishes are dated back to the middle of Jurassic period.

Polypterids have been living on our planet for quite a long time. It is supposed, that their first species appeared in the last period of Mesozoic era, which means that the genus has existed for about 60 million years!

Modern Polypterids species occur in freshwater basins in Africa and India. The fish prefers muddy water and silted bottom, it can even live in bogs. The fish navigates in water (which is not transparent) due to its sense of smell, at that it has quite poor sight.

Some Polypterids species are constant tank dwellers. Among them are the following: barred bichir (P. delhezi), ornate bichir (P. ornatipinnis), marbled bichir (P. palmas), and senegal bichir or gray bichir (P. senegalus).


Since an ancient fish is supposed to look ancient, fishes body looks quite archaic. The fish skeleton resembles that of a shark and it is not made from bones, but from cartilages.

Maximum length of Polypterids species body is over 100 cm (39 in), but most of them aren’t longer than 25 cm (9.8 in).

Average lifespan is about 10 years and it highly depends on tank conditions.

The body is covered with diamond shaped flexibly joined scales. If Polypterids skin stays wet, it can stay out of water for some time. The skin is very strong and it is kind of armor, that protects the fish from other carnivorous species.

The dorsal fin consists of a row of 5-18 small fins, which defined the name of Polypterids. Pectoral fins of the fish evolve from a fleshy blade, which visually resembles lobe-finned fishes construction (however, their skeletons are completely different).

Like paleobiospecies of the fishes found, Polypterids can breathe with atmospheric air. Ray-finned fishes have quite specific air-bladder. It consists from two sections (right one which is large and left one, which is smaller).

Both sections are connected with intestinal tract by means of common channel and actually act as an additional respiratory organ (apart from grills).

This allows Polypterids to gasp some air from water surface, which is quite useful when living in water basins with low oxygen content. At that (unlike lungfishes) the fish doesn’t have choanas.

Difficulties in keeping

Bichirs have been living in tanks since the beginning of the 20-th century. Keeping the fish in a tank doesn’t seem to be a difficult task: these species are not demanding and are quite enduring, they can live in rather dirty water.

However, this is a predator and only large fishes can be their tank mates. Another thing is, that the fish is a slow one and it takes a while for it to find the food, which can be a problem when dwelling together with fast fishes in the tank – bichirs may starve.

This fish can be recommended to beginners, if the latter will be capable to provide it with proper tank conditions, since yet it is rather specific and unusual fish.

Keeping in a tank

Scientific namePolypteridae
Common NameBichir fish, dragon fin fish, dinosaur bichir, dragonfin fish
Tank size50 US gallons (200 L) and more
Temperature24-26 °C (75,2-78,8 °F)
Size25 cm (9.8 in)
Lifespan10 years

Bichirs is quite strong and healthy fish. To keep one you will need a tank of at least 50 US gallons (200 L) capacity and it’s better to be larger.

The cover is a must for such a tank! Bichirs can not only jump out of the tank, but also crawl out of it. There should be some air between the cover and tank water surface, otherwise the fish won’t be able to breathe.

Here are proper tank water parameters for Polypterids keeping: water acidity pH should be about 7, the fish is not demanding as for the water hardness. It will feel comfortable both in soft and hard water, though it’s better not to take chances with extremely hard water (higher than 20).

Despite the fact that Polypterids itself doesn’t need any aeration in the tank, the tank ecosystem will benefit from it.

Tank decorations may be of any kind you like. Stones, caves, castles will do. Live tank plants are desirable, but not necessary.

Since bichirs is mostly a bottom-feeder, the tank bottom substrate should be easy in care and cleaning. It’s better be a thin layer of sand, though small grained gravel will do as well. But the latter is less natural like for the fish and it will be more difficult for the fish to feed from it.

Some aquarists advise to keep bichirs in an empty tank, to decrease their territory dependence. But the view of the fish swimming in a tank without decorations or caves is a bit depressing. On the other hand, the fish looks more fascinating when it is slowly creeping up between tank plants or stones in a good decorated tank.

Smooth stones, snags, caves will perfectly do as tank decorations. You can also use ceramic and plastic tubes, but they look less natural.

Filtration in tank – it’d be excellent to have a powerful canister filter with ability to clean water using both mechanical and biological filtration. Though the fish is not quite active and it doesn’t leave much litter if compared to other fishes, but protein food is a source of many small leftovers, that make tank water toxic very fast without proper filtration.


Bichirs is a predator fish and you should feed it basically with live food: bloodworm, frozen shrimps and calamary, small fishes, pieces of ox heart and meat, earthworm. The fish may also feed on artificial food, but this kind of diet is not natural for it.

The fish feature is that it eats slowly, since in the wild the fish goes hunting at night when its prey is not active. So, if you noticed that some tank dwellers disappear at night, this may be the reason.

Compatibility and tank mates

Any fish will do as Polypterids tank mate, the main thing is that it shoudln’t fit into its mouth. Bichir never attack large healthy fish without a reason.

Fishes of the same size as fish will do as its tank mates. These can be oscar, blood parrot, green terror and so on. I wouldn’t recommend to keep together with flowerhorn, since the latter may kill even such a protected fish.

Sometimes bichir may even attack the fish of larger size, though usually this happens due to the bad eyesight.

Gender differences: male vs female

It is difficult to see between the male and female. As for the indirect distinctive features, these are: wider and thicker anal and dorsal fin of the male, while females are usually larger in size. As for the young species – it’s impossible to see males and females between them.


In a home aquarium fishes breed quite seldom. The species you see on sale were caught in the wild.

Senegal bichir (P. senegallus)

This is one of the most active and less timid Polypterids species. It actively swims almost all the time, it is curious and persistent. The fish doesn’t show aggression towards its kind and other tank dwellers if the latter are large enough.

The fish is reasonably large – up to 35.5 cm (14 in). I must say, that this is the fish you should get when you start getting to know Polypterids species.

Ornate bichir (Polypterus ornatipinnis)

This is one of the most appealing Polypterids fishes. But unfortunately, it is very timid and you will seldom see it during a day, except when it comes out for food.

Besides the fish is more aggressive towards its kind and may take food from other fishes. It grows to become larger than the previous fish – 60 cm (24 in) in length and therefore it requires more roomy tank. This is a very strong predator fish capable of catching even a fast fish.

Saddled bichir (Polypterus endlicheri)

Polypterus endlicheri is a large and strong species, that grows to become up to 30 long (75 cm) in the wild.

It is not very active during a day, it mainly slowly swims looking for food. Considering the size, it’s better to keep it in a separate tank and feed with live food (once or twice a week).

Barred bichir (Polypterus delhezi)

Polypterus delhezi inhabits in Kongo river. It is not very active during a day and it spends its time in shelters.

Rope fish (Erpetoichthys calabaricus)

Erpetoichthys calabaricus – follow the link to find more about this fish.

About author: Sergey Schulz

Sergey is a founder and author of He’s been fond of aquarium husbandry since his early childhood. His favorite aquariums are biotopes (Amazon River), with Echinodorus and freshwater angelfish. However, through the years he’s had experience of keeping almost all types of freshwater fish and shrimps.