What Bichir Are and Why They Matter to Aquarists

Bichir are ancient freshwater fish native to Africa, recognizable by their elongated bodies, rows of small dorsal fins, and primitive appearance that has changed little in millions of years. They belong to the family Polypteridae and are sometimes called "dinosaur fish" because of their prehistoric look. Unlike most aquarium fish, bichir have a lung-like organ called a labyrinth that lets them breathe air at the water's surface, which means they can survive in low-oxygen conditions that would stress other species.

Bichir appeal to experienced aquarists because they have distinct personalities, live for 10 to 20 years depending on species, and occupy a different ecological role than typical tank fish. They are bottom-dwellers and hunters, so they require specific tank conditions and tank mates that can coexist with a predatory fish. Their unusual biology and behavior make them a long-term commitment rather than a beginner's fish.

Key Takeaways

  • Bichir are African freshwater fish with an air-breathing organ, allowing them to survive in tanks with lower oxygen levels than most fish need.
  • They require tanks of at least 75 gallons for smaller species and 125+ gallons for larger ones, with hiding spots, low water flow, and a secure lid because they can climb out.
  • Bichir are carnivorous hunters that will eat smaller fish and invertebrates, so tank mates must be large enough not to be prey.
  • Different bichir species vary in size, temperament, and care needs, so researching your specific species before purchase is essential.
  • Bichir are not regulated as invasive in most U.S. states, but some states and countries restrict or ban them, so check local rules before obtaining one.

Common Bichir Species and Their Size

The Senegal bichir is the smallest and most commonly available species, reaching 12 to 18 inches in captivity. It is relatively docile compared to other bichir and tolerates a wider range of tank mates, making it the most suitable choice for aquarists new to the species. Senegal bichir are gray or brown with faint banding and are hardy in established tanks.

The ornate bichir grows to 18 to 24 inches and displays more striking coloration with yellow or white bands on a darker body. They are more aggressive than Senegal bichir and will hunt anything they can fit in their mouth. The endlicheri bichir (also called the West African bichir) reaches 24 to 30 inches and is one of the most aggressive species, requiring very large tanks and careful tank mate selection.

The palmas bichir is a smaller species, staying around 12 inches, and is less commonly imported. The Congo bichir can exceed 30 inches and is rarely kept in home aquariums because of its size and aggression. Before purchasing any bichir, confirm the adult size of your specific species and ensure your tank can accommodate it for its entire lifespan.

Tank Setup and Water Conditions

Bichir need tanks large enough to move freely without constant turning. A 75-gallon tank is the minimum for a Senegal bichir, while larger species like ornate or endlicheri bichir require 125 gallons or more. The tank should be longer rather than tall, since bichir are bottom-dwellers and do not use vertical space the way other fish do. A 4-foot-long tank is better than a tall 3-foot tank of the same volume.

Bichir are sensitive to strong water flow, so use a filter with an adjustable output or position the intake and return to create gentle circulation rather than a current. They prefer slightly acidic to neutral water with a pH between 6.5 and 7.5, and a temperature range of 72 to 82 degrees Fahrenheit. Weekly partial water changes of 25 to 30 percent keep nitrate levels low, which bichir are sensitive to over time.

Hiding spots are essential. Provide PVC pipes, driftwood, caves, or dense plants where the bichir can rest during the day. Bichir are nocturnal hunters and will spend daylight hours in shelter. A secure lid is non-negotiable because bichir can and will climb out of tanks, especially if stressed or hunting. They have been found on floors several feet away from their tanks.

Feeding and Predatory Behavior

Bichir are carnivorous and will not eat standard flake or pellet food. They hunt live or frozen prey, including small fish, shrimp, bloodworms, and earthworms. Most bichir will accept frozen foods once acclimated, which is safer and more convenient than live prey. Frozen bloodworms, krill, and small frozen fish are reliable staples. Feed juveniles daily or every other day, and reduce feeding frequency to three to four times per week as they mature.

Bichir are ambush predators and will eat any fish small enough to fit in their mouth. Tank mates must be large, fast, or armored enough to avoid predation. Plecos, large catfish, and other bottom-dwellers of similar size can coexist with bichir, but small tetras, rasboras, and shrimp will be hunted. Never house bichir with fish you are not willing to lose.

Overfeeding is common because bichir are opportunistic eaters and will consume more than they need. A bichir's stomach is small relative to its body, so feed portions about the size of its eye, two to four times per week for adults. Watch for bloating or constipation, which can occur if feeding is excessive or if the diet lacks variety.

Bichir Behavior and Temperament

Bichir are solitary and territorial, especially as they mature. Two bichir in the same tank will fight, particularly if they are the same species or similar size. Housing them together is not recommended except in very large systems with multiple hiding areas, and even then aggression is likely. Most aquarists keep one bichir per tank.

Bichir are intelligent and recognize their owners, often coming to the glass when they see you approach. They have distinct personalities—some are bold and active, while others are shy and nocturnal. Over time, many bichir become tame enough to hand-feed, though their teeth are sharp and accidental bites can occur. Handle them gently and infrequently to avoid stress.

Bichir occasionally gulp air at the surface, which is normal behavior and not a sign of poor water quality. However, if a bichir spends most of its time at the surface or appears lethargic, check ammonia, nitrite, and nitrate levels. They are hardy fish but do not tolerate sudden changes in water chemistry or temperature.

Legal Status and Where to Find Bichir

Bichir are legal to own in most U.S. states, but some states and countries restrict or ban them. California, New York, and a few others have restrictions on certain species or require permits. Some countries classify bichir as invasive or potentially invasive and prohibit import or ownership. Before purchasing a bichir, check your state's fish and wildlife regulations or contact your local aquarium store to confirm legality in your area.

Bichir are available through specialty aquarium stores, online retailers, and occasionally at general pet stores. Prices vary by species and size, ranging from $20 to $100 or more for captive-bred fish. Wild-caught bichir are less common in the hobby but may appear at specialty importers. Captive-bred fish are generally hardier and less stressed than wild-caught specimens.

When purchasing a bichir, inspect it for visible injuries, fin damage, or signs of disease. A healthy bichir should be alert, have clear eyes, and show interest in food. Avoid fish that appear emaciated or have cloudy eyes, as these are signs of poor health or long transport stress.

Breeding Bichir in Captivity

Breeding bichir in home aquariums is rare and difficult. They require very large tanks, specific water conditions, and a compatible pair, which is hard to establish since bichir are territorial. Spawning has been documented in captivity but is not common in the hobby. Most bichir sold in the aquarium trade are wild-caught or bred in commercial facilities in Asia or Africa.

If you are interested in breeding, research your specific species thoroughly and connect with experienced bichir keepers through online forums or aquarium clubs. Breeding requires patience, space, and a willingness to accept failure. For most aquarists, keeping a single healthy bichir is the realistic goal.

Frequently Asked Questions

Can bichir live with goldfish or koi?

No. Bichir are carnivorous hunters and will attack goldfish and koi, especially juveniles. Even large goldfish are at risk because bichir hunt by ambush and can injure or kill larger fish. Keep bichir only with fish that are too large to be prey or armored enough to defend themselves.

How often should I do water changes for a bichir tank?

Perform a 25 to 30 percent water change weekly. Bichir are sensitive to nitrate accumulation, so consistent water maintenance is important. If the tank is heavily stocked or the filter is undersized, increase to twice-weekly changes. Test water parameters monthly to monitor ammonia, nitrite, and nitrate levels.

Do bichir need a heater?

Yes, unless your room temperature stays between 72 and 82 degrees Fahrenheit year-round. Most homes require a heater to maintain this range, especially in winter. Use a reliable aquarium heater with a thermostat and monitor temperature daily with an accurate thermometer.

What should I do if my bichir stops eating?

First, check water parameters—ammonia, nitrite, and nitrate levels can cause appetite loss. Confirm the tank temperature is in the correct range. If water quality is good, the bichir may be stressed by tank mates, a recent move, or a change in routine. Try offering different foods and observe for other signs of illness. If the fish remains inactive or shows visible damage, isolate it in a hospital tank and monitor closely.

Can bichir live in a planted tank?

Yes, but bichir will uproot or damage most plants as they move along the bottom. Hardy plants like Java fern or Anubias tied to driftwood are more likely to survive. Expect some plant damage regardless. If a heavily planted tank is your goal, bichir may not be the right choice for that setup.