Top 15 Bichir Tank Mates: What Works With This Prehistoric Predator

Last Updated: October 3, 2026

Most people who lose fish to a bichir never see it happen. The bichir lies under a piece of wood all day and the tank looks fine, then a fish is missing in the morning. Bichirs are nocturnal ambush predators. They’re not aggressive in a fight club way. I put the Senegal bichir in A tier on my monster fish tier list because they’re pretty chill if you don’t have any tiny fish fluttering around like snacks on parade.

If a fish fits in their mouth, it’s going to be dinner.

Understanding Them

Bichirs are carnivores, and shrimp and other invertebrates are on the menu right next to fish. They also live up to 15 years (so you’re picking roommates for the long haul). These bottom dwellers use both gills and lungs to breathe.

Overview Of Types

People ask me how big they get. It depends on the species. A full revision of the bichir family published in 2019 (Moritz and Britz) recognises two genera, Polypterus and the ropefish. Here are four you’ll see for sale, with average adult sizes.

• Dinosaur Bichir – 12 to 14 inches (30 to 36 cm)
• Ornate Bichir – 24 inches (61 cm)
• Saddled – 30 inches (76 cm)
• Delhezi – 14 inches (36 cm)

For this post, we’ll focus on the Dinosaur Bichir, which is the same fish as the Senegal bichir (Polypterus senegalus). They max out at around 12 to 14 inches (30 to 36 cm). Other Bichirs need larger tanks and more careful tank mate selection. Viewers under my monster fish tier list made the same point: the Senegal is the smallest one, and some of the lower jaw bichirs get very aggressive and grow well past 16 inches (41 cm).

Ambush Predator Nature

A bichir will eat your smaller fish with the serene confidence of something that has outlasted every mass extinction event. The safest tank mates live in the middle and top of the tank and are up during the day, when the bichir isn’t. Silver dollar fish are the textbook example. The bottom dwellers on this list share the floor with the bichir, so they need hiding spots of their own.

Feed frozen food separately to avoid aggression. The night hunting also rules out the typical fast schooling fish like Danios, because a bichir will sneak up on them and eat them.

What People Get Wrong About Bichir Tank Mates

People watch a bichir for chasing and flaring, like they would an aggressive fish. It ignores a fish for weeks, then the fish is gone overnight. A fish under half the bichir’s length gets eaten eventually, no matter how fast it swims. A Dinosaur Bichir runs 12 inches (30 cm) and up, so that means 6 inches (15 cm) at the very least. A 6 inch fish only just clears it, and viewers have lost fish that size too.

The Biggest Mistake: Buying the Right Fish at the Wrong Size

Any fish on this list is a problem if you buy it small. A juvenile Bala Shark is a compatible species as an adult and a snack right now. Buy tank mates that are already at least half your bichir’s length.

What Viewers Told Me Went Wrong

I haven’t kept bichirs in my own tanks. The most useful comments on my bichir tank mates video are the failures. Out of 66 comment threads, 7 commenters reported a bichir eating or killing its tank mates. The reports on my 15 Best Bichir Tank Mates video include two fire eels, an adult African Butterfly Fish, two Severums and a large goldfish, and one just wrote “Mine ate everything i put with it” (@ericliethen1089, same video). And fish too big to swallow still end up with chewed fins and tails, according to one of them.

So eels and Severums are cautions now, and so is the African Butterfly Fish. All three depend on which bichir species you have and how big it is. The comments and my answers are further down the page.

Ideal Aquarium Size And Water Parameters

The minimum tank size for a Dinosaur Bichir kept with tank mates is 90 to 100 gallons (341 to 379 L). For water temperature, aim for 74 to 82°F (23 to 28°C), with a pH level of 6.2 to 7.8. Give them a sandy substrate and plenty of hiding spots. Big fish make massive poops, and they are messy eaters.

Bichirs leave aquatic plants alone, so you can plant the tank unless you’re adding Silver Dollars.

Top 15 Bichir Tank Mates

Fifteen fish make this list. None of them is a guarantee. Bichirs vary, and the size you buy matters more than the name on the tag. The sizes listed are adult sizes, so check the size you’re buying. The Min Tank column is for that fish on its own. Add a bichir and the 90 to 100 gallon (341 to 379 L) minimum applies.

Expert Take

Bichirs look slow and docile during the day, so people assume they’re safe with a much wider range of fish than they actually are. They eat anything that fits in their mouth, and their mouths are larger than they look. Size is the only reliable protection. — Mark Valderrama, AquariumStoreDepot

Quick-Reference Comparison Table

1. Eels

Ease: 7/10. Works until the bichir outgrows it.

• Scientific Name: Various
• Adult Size: 6 to 150+ inches (15 to 381+ cm)
• Water Temperature: 72°F to 82°F (22°C to 28°C)
• Minimum tank size: 20 – 55+ gallons (76 – 208+ L)
• Care Level: Moderate
• Diet. Carnivore
• Origin. Various
• Swimming Level. Bottom

Eels and bichirs both stay on the bottom, like to hide, and eat compatible diets. Both need lots of shelter and hiding spots. A viewer’s fire eel was fine for years until the bichir outgrew it. So look at how big your bichir is going to get before you try this one.

2. Silver Dollars

Ease: 9/10. One of the safest choices for this tank setup.

• Scientific Name: Metynnis argenteus / Metynnis hypsauchen
• Adult Size: 6 inches (15 cm)
• Water Temperature: 72°F to 82°F (22°C to 28°C)
• Minimum tank size: 75 gallons (284 L)
• Care Level: Easy
• Diet. Omnivore
• Origin. South America
• Swimming Level. Middle to top

Silver Dollars are peaceful, social fish. They’re very fast and large, which keeps them from getting targeted by your Bichir. Keep them in a school of six or more. You won’t be able to keep plants with Silver Dollars, because they’re going to eat most varieties.

3. Hoplo Catfish

Ease: 7/10. A peaceful fit, but bichirs bite catfish whiskers.

• Scientific Name: Megalechis thoracata
• Adult Size: 6 inches (15 cm)
• Water Temperature: 72°F to 82°F (22°C to 28°C)
• Minimum tank size: 40 gallons (151 L)
• Care Level: Moderate
• Diet. Omnivore
• Origin. South America
• Swimming Level. Bottom

Hoplo Catfish work with Bichirs because they’re peaceful, big enough, and adaptable. These armored bottom dwellers grow to 6 inches (15 cm). For the pair, go with a minimum of 90 to 100 gallons (341 to 379 L), sand, and plenty of hiding spots.

Bichirs have a habit of biting the whiskers off a catfish. That puts this one on the riskier end. Watch closely and act right away if a fish is attacked.

4. Oscars

Ease: 7/10. Depends on the bichir species. The largest ones are the riskiest for the Oscar.

• Scientific Name: Astronotus ocellatus
• Adult Size: 12+ inches (30+ cm)
• Water Temperature: 74°F to 81°F (23°C to 27°C)
• Minimum tank size: 120 gallons (454 L)
• Care Level: Moderate
• Diet. Omnivore
• Origin. South America
• Swimming Level. Middle to top

Oscars are large and hardy. Oscars are S tier on my monster fish tier list. They aren’t mean, just constantly hungry and bad at impulse control, and anything small enough to fit in their mouth is a snack. One adult Oscar needs 120 gallons (454 L) minimum for long-term keeping, and that’s before you add a bichir.

5. Tinfoil Barb

Ease: 7/10. Good choice, if your tank is 6 feet (1.8 m) long.

• Scientific Name: Barbonymus schwanenfeldii
• Adult Size: 14 inches (36 cm)
• Water Temperature: 72°F to 77°F (22°C to 25°C)
• Minimum tank size: 75 gallons (284 L)
• Care Level: Moderate
• Diet. Omnivore
• Origin. East Asia
• Swimming Level. All

Tinfoil barbs are active schooling fish that get quite large, and they coexist peacefully with Bichirs. The 75 gallons (284 L) is for the barbs alone. With a bichir, you need at least a 6 foot (1.8 m) long tank.

Hard Rule: Any fish smaller than half the bichir’s body length is potential prey. Bichirs are most active in low light, and at night they take fish they ignored all day.

6. Knife Fish

Ease: 6/10. Works, but it needs a big tank and plenty of cover.

• Scientific Name: Apteronotus albifrons
• Adult Size: 14+ inches (36+ cm)
• Water Temperature: 73°F to 82°F (23°C to 28°C)
• Minimum tank size: 100 gallons (378 L)
• Care Level: Carnivorous
• Diet. Omnivore
• Origin. South America
• Swimming Level. Middle to Bottom

A Knife Fish needs to hide away from light during the day. It needs 100 gallons (378 L) on its own. With a bichir, plan on at least 125 gallons (473 L), with plenty of cover for both.

7. Bala Shark

Ease: 7/10. Great as adults, but a snack when small.

• Scientific Name: Balantiocheilos melanopterus
• Adult Size: 12 inches (30 cm)
• Water Temperature: 75°F to 82°F (24°C to 28°C)
• Minimum tank size: 125 gallons (473 L)
• Care Level: Moderate
• Diet. Omnivore
• Origin. Southeast Asia
• Swimming Level. Middle to Top

Full-grown Bala Sharks are some of the better companions for Bichirs. They stay in the middle and upper water. They have to be in groups of five or more, in at least a 125 gallon (473 L) tank, bare minimum.

A juvenile is a snack for a Bichir, so don’t buy them small.

8. Giant Gourami

Ease: 7/10. An easy pairing if you own a tank big enough, and most people don’t.

• Scientific Name: Osphronemus goramy
• Adult Size: 18 inches (46 cm)
• Water Temperature: 69°F to 86°F (21°C to 30°C)
• Minimum tank size: 200 gallons (757 L)
• Care Level: Moderate
• Origin: Southeast Asia
• Swimming Level – Middle to Top

Giant Gouramis are relatively placid fish that reach 18 inches (46 cm), and they do well with Bichirs in a big enough tank with places to hide. I marked it down on two tier lists. Males are territorial. And a viewer corrected me on lifespan: they say 20 years, not just 10.

A Giant Gourami needs 200 gallons (757 L) or more. That keeps it out of reach for many aquarists, but it’s a great combination if you have the tank.

9. Arowana

Ease: 6/10. Works, but only in 250 gallons (946 L) or more.

• Scientific Name: Osteoglossum bicirrhosum
• Adult Size: 2+ feet (60+ cm)
• Water Temperature: 75°F to 82°F (24°C to 28°C)
• Minimum tank size: 250 gallons (946 L), 8 foot (2.4 m) long tank
• Care Level: Advanced
• Origin: Amazon
• Swimming Level – Middle to Top

Arowanas are a good companion for Bichirs in a tank of 250 gallons (946 L) or larger. If it’s smaller than the Arowana’s mouth, it’s going to get inhaled. They’ll also jump 2 to 3 feet (0.6 to 0.9 m) into the air if you don’t cover the tank properly.

10. Denison Barbs

Ease: 7/10. A caution. A full-grown one is under the half-length rule.

• Scientific Name: Sahyadria denisonii
• Adult Size: 4 inches (10 cm)
• Water Temperature: 72°F to 79°F (22°C to 26°C)
• Minimum tank size: 40 gallons (151 L)
• Care Level: Moderate
• Origin: Southern India
• Swimming Level – Middle to Top

This is the riskiest fish on the list. A full-grown Denison Barb is 4 inches (10 cm), which is under half the length of an adult Dinosaur Bichir, so it’s potential prey. You need a proper school, meaning six or more, and enough room for them to swim.

11. Elephant Nose Fish

Ease: 6/10. Works, but it needs sand and its own places to hide.

• Scientific Name: Gnathonemus petersii
• Adult Size: 9 inches (23 cm)
• Water Temperature: 73°F to 82°F (23°C to 28°C)
• Minimum tank size: 55 gallons (208 L)
• Care Level: Difficult
• Origin: Africa
• Swimming Level – Bottom of the tank

Elephant Nose Fish come from Africa, just like bichirs, and the two co-exist well in the right tank. Use sand, not gravel substrates, to protect that trunk. Give both generous space and places to hide to prevent aggression.

12. African Butterfly Fish

Ease: 7/10. A caution. It lives at the surface, but a viewer lost a full-grown one.

• Scientific Name: Pantodon buchholzi
• Adult Size: 6 inches (15 cm)
• Water Temperature: 75°F to 82°F (24°C to 28°C)
• Minimum tank size: 30 gallons (114 L)
• Care Level: Moderate
• Origin: Africa
• Swimming Level – Top

African Butterfly Fish sit just under the surface, so the two mostly stay out of each other’s way. They’re Olympic level jumpers, and not a beginner friendly fish at all. Keep the tank covered. It isn’t a guarantee, though. One viewer reported a Senegal eating a full-grown one.

13. Clown Loaches

Ease: 6/10. Works, but a group needs 100 gallons (378 L) at the very least.

• Scientific Name: Chromobotia macracanthus
• Adult Size: 12 inches (30 cm)
• Water Temperature: 75°F to 85°F (24°C to 29°C)
• Minimum tank size: 100 gallons (378 L)
• Care Level: Difficult
• Origin: Indonesia
• Swimming Level – Bottom

Clown Loaches have to be kept in a group of five or more, and five loaches that reach 12 inches (30 cm) need 100 gallons (378 L) at the very least. That’s why they landed in D tier on my loach tier list. Not because they’re bad fish, but they’re completely inappropriate for the vast majority of aquarists.

14. Severum

Ease: 7/10. More of a caution. Know how big your bichir is going to get.

• Scientific Name: Heros severus
• Adult Size: 8 inches (20 cm)
• Water Temperature: 75°F to 84°F (24°C to 29°C)
• Minimum tank size: 75 gallons (284 L)
• Care Level: Moderate
• Origin: South America
• Swimming Level – Bottom to Mid

Severums are that rare monster fish you can actually trust in a semi-peaceful community tank, provided you don’t throw in snack-sized tank mates. They grow up to 8 inches (20 cm).

A Severum needs 75 gallons (284 L) on its own. The pair needs 90 to 100 gallons (341 to 379 L), with a cave or piece of driftwood the bichir can call its own. I used to call this one a slam dunk, but after a viewer lost two of them I’d call it a caution. Check the size of both fish before you try it.

15. Leopard Bush Fish

Ease: 7/10. Fine with the smaller bichir species.

• Scientific Name: Ctenopoma acutirostre
• Adult Size: 6 inches (15 cm)
• Water Temperature: 72°F to 82°F (22°C to 28°C)
• Minimum tank size: 50 gallons (189 L)
• Care Level: Moderate
• Origin: Africa
• Swimming Level – Bottom to Mid

The Leopard Bush Fish is another ambush predator. It needs plenty of hiding places and live or frozen food like bloodworms and brine shrimp.

Larger Bichirs eat them. Keep this one with a Dinosaur Bichir only. A full-grown Leopard Bush Fish only just clears the half-length rule.

Honorable Mentions

These didn’t make the main 15, but you can consider them.

• Convict Cichlid
• Pink Convict Cichlid
• Blue Acara
• Peacock Bass – they hit up to 30 inches (76 cm)

People in the comments have added their own, like ropefish, Raphael catfish, firemouths, and angelfish. The angelfish reports are mostly good, but one person lost large angels that were chewed on and died.

Bad Choices

Some of these will eat or hurt your bichir. The rest fit in its mouth.

Fish that eat or hurt the bichir:

• Red tail catfish – here the bichir is the meal. I’ve been asked about this pairing twice in the comments, and my answer is no, the catfish will eat them. A gulper catfish is smaller and still will eat Bichirs. Gulpers are F tier on my monster fish tier list because they can and will attempt to swallow fish as big as themselves
• Plecos – they will suck on the slime coat of the Bichir. A few viewers say bristlenose and blue phantom plecos worked for them

Fish the bichir eats:

• Small schooling nano fish
• Danios – while fast, they will get ambushed
• Small cichlids
• Corydoras catfish – too small
• Bettas
• Shrimp

African cichlids come up in the comments too. A couple of people keep Senegals in African cichlid tanks without trouble, one of them with a dozen polar blues in a 90 gallon (341 L).

Mark’s Pick: Among cichlids, large ones like the green terror are the safest tank mates. They’re big enough to ignore and tough enough to defend themselves if the bichir gets curious. The Oscar is off this pick, and the Severum is a caution. Bichirs are risky in general because they fit a lot of fish in their mouths.

Which Bichir Tank Mate Should You Choose?

• Oscars depend on the bichir species. The largest bichir species are the riskiest for the Oscar. Severums are more like a caution, because bichirs do vary in size.
• Silver Dollars and Tinfoil Barbs both work. Only go with Tinfoils if your tank is 6 feet (1.8 m) long.
• Several viewers with Senegals told me this list runs big. A 40 to 50 gallon (151 to 189 L) is under the 90 to 100 gallon (341 to 379 L) minimum for a Dinosaur Bichir kept with tank mates.
• An Ornate or Saddled Bichir needs a larger tank and more careful tank mate selection.

What Viewers Ask About Bichir Tank Mates

I updated this page in October 2026 with viewer reports from the channel. The comments are from the video. My answers were written for this page.

J

@justinruim5262 commenting on my 15 Best Bichir Tank Mates video

With regards to the eels, While they can work out you have to monitor and make sure that they are close to the same size. I have a friend from work who kept a fire eel with a bichir for years without incident and then one day the bichir grew just a little bigger than the fire eel and ate it. …

@AquariumStoreDepot Mark’s answer

It’s more like a caution, because bichirs do vary in size.

P

@pin3_exp427 commenting on my 15 Best Bichir Tank Mates video

We just got two severum and my bichirs ate them 😢

@AquariumStoreDepot Mark’s answer

Sorry to hear that. Severums are more like a caution, because bichirs do vary in size.

T

@That_One_Bro commenting on my 15 Best Bichir Tank Mates video

What about a redtail catfish??

@AquariumStoreDepot Mark’s answer

They will eat Bichirs. A gulper catfish is smaller and still will eat them.

M

@MS-Varun commenting on my 15 Best Bichir Tank Mates video

i dont recomend adding oscar to bichir … one day i saw oscar eating the bichir even tho there are same size

@AquariumStoreDepot Mark’s answer

It depends on the bichir species. The largest bichir species are the riskiest for the Oscar.

Frequently Asked Questions

Who Is This Setup Right For?

Good Fit If:

• Your tank is 90 to 100 gallons (341 to 379 L) or larger, and everything in it is already at least half the bichir’s length, which is 6 inches (15 cm) or more for a Dinosaur Bichir
• You want a prehistoric-looking display fish to anchor a large predator tank
• A centerpiece fish you mostly see after dark doesn’t bother you

Avoid If:

• You have fish under half the bichir’s length. They get eaten eventually, and it happens at night
• You want small schooling fish like Danios. The bichir sneaks up on them and eats them
• You can’t give other bottom dwellers their own shelter. Eels and Elephant Nose Fish need hiding spots of their own

Closing Thoughts

When you pick tank mates, look at the size, aggression level, and needs of each fish. Like I say at the end of the video: size matters, attitude is everything, and a well paired tank is a happy aquarium. Every Bichir is different. Some are model citizens and some are absolute terrors, so have a backup plan before you add anything.

The rule from the top doesn’t change. If a fish fits in a bichir’s mouth, it’s dinner.

📘 Want to learn more? This article is part of our complete Freshwater Fish Guide, your ultimate resource for freshwater species, care tips, tank setup, and more.

Recommended Video

• About the Author
• Latest Posts

Mark Valderrama

I’m Mark Valderrama, founder of Aquarium Store Depot and a fishkeeper with over 25 years of hands-on experience. I started in the hobby at age 11, worked at local fish stores, and have kept freshwater tanks, ponds, and reef tanks ever since. I’ve been featured in two best-selling aquarium books on Amazon and built this site to share practical, experience-based fish keeping knowledge.

• 11 Types of Freshwater Eels: What They Actually Are (And What to Expect)
• 15 Freshwater Crabs for Your Aquarium (Honest Notes on Every Species)
• Types of Freshwater Catfish: 10 Great Species (And 4 to Avoid)