dinosaur

The dinosaur eel is the common name for the Gray Bichir, Senegalese polypterus, although it is a fish and not an eel. There are more than a dozen species of this fish, but the Gray Bichir or Senegalus Bichir is the most common and popular among aquarists. This Bichir is covered in dark gray horizontal bands that become paler as the fish grows. Some Bichirs can reach over three feet in length, although most species, including the Senegalus Bichir, grow to around a foot.

natural habitat

In their natural habitat, they can be found in lakes, rivers, floodplains, and swamps of Africa, especially the Congo River and the Nile. They are capable of surviving in low-oxygen waters and can move around in search of food or to find other moist areas in your house dry in dry season.

Characteristics

The misnomer dinosaur eel (hereafter Bichir) comes from the prehistoric appearance of this elongated fish. Its snake-like body is covered in thick, bone-like scales made of an enamel-like substance called ganoin, resembling the now-extinct early ray-finned fish. It has a distinctive series of up to 18 dorsal finlets, each with a sharp spine, which stand up when agitated. The fleshy pectoral fins, which control the slow movement of the fish, are attached behind and below the gill openings. It can also travel on land using its strong pelvic fins. Bichirs can also breathe air through a lung-like modification to their swim bladder. Other features include a pair of blowholes, a long lower jaw, and external nostrils that protrude from the nose to allow the Bichir to hunt by smell as its eyesight is poor. Females tend to be larger than males, while adult males have thicker dorsal spines and broader anal fins.

Diet

Bichirs are predatory and essentially carnivorous and will attack and feed on small fish that are easy to swallow, as well as slow moving fish. They will also eat insects, crustaceans, and frogs. Since they are nocturnal, they will feed mainly at night.

Breeding

After a series of energetic spinning movements, the male Bichir fertilizes the eggs by enveloping the female’s genital opening with his anal and caudal fins. He then spreads the eggs with flicks of her tail. However, it is difficult to get Bichirs to breed in captivity. Some aquarists have noticed that even if a male and female are present, the male is often unresponsive and will not fertilize the eggs the female releases.

aquarium size

Due to the Bichirs’ growth length and their need to breathe air, it is important that they be housed in long tank aquariums that are not too deep, possibly even in a fish tank table. Aim for an aquarium that is at least three times the adult size of the Bichir you own or plan to purchase. Choose fish tank aquariums that are no more than eighteen inches deep and do not fill completely with water. This is important as Bichirs need to be able to breathe air and therefore need to be able to quickly swim to the surface and back to the bottom where they dwell.

Being able to utilize oxygen from the air allows Bichirs to survive out of water for several hours. Given this and the fact that they have an instinct to leave one location in search of food in another, having a well-fitting lid on your aquarium is recommended!

aquarium decoration

A thin layer of soft sand or gravel is fine as a substrate. Bugs also like hiding places, especially as they prefer to stay out of the light during the day. Therefore, it is much nicer for them to have robust plants, rocks, and tunnels that allow them to display more natural behaviors. Plants attached to wood work best, as Bichirs tend to displace plants rooted in the substrate due to their size and when foraging.

water conditions

As they are freshwater tropical fish, Bichirs require a temperature of 75-85 F. They like a pH of 7 or slightly below and prefer water that is a bit hard. Of course, frequent water changes are important to ensure good water quality in your tropical freshwater aquariums.

aquarium lighting

Bugs are nocturnal, so they will normally be torpid during the day and active at night. Instead of turning off your aquarium lights entirely, provide the appearance of natural dusk by installing a blue moonlight bulb so you too can experience some action from your Bichir.

Feeding

Being carnivores, Bichirs love to be fed baitfish, mussels, shrimp, and bloodworms. They will also readily accept frozen foods. Some aquarists have tried to encourage dry food by feeding them only until hunger overcomes them and have found that they can adapt well. However, I would like to mention that this is not their natural diet.

tank mates

Given the large size of Bichirs and their predatory nature, it is extremely important to pair them with suitable tank mates. Don’t keep them with fish smaller than three inches that can provide a prepared meal! It is best to pair Bichirs with larger fish as they will not be as bothered by fish that cannot swallow. Siamese tigerfish, angelfish, large barbs, cichlids, and knifefish are all possible tank mates. It has been observed that suctionmouth catfish tend to suck on the skin of Bichirs, which irritates them, so keeping both types of bottom-dwelling fish is not recommended. Also avoid pairing them with overly aggressive species. In a very large tank it will be possible to keep several Bichirs together, as long as they are the same size. In general, they should tolerate each other, as well as fight over food!

To keep or not to keep?

Bichirs are interesting specimens of fish, but be aware of all the issues associated with keeping them, especially tank size and any other freshwater tropical fish you have or plan to keep. Bichirs also cost more to keep than other fish, although they are a very hardy breed. Keeping Bichirs in a suitable environment requires careful planning!