Can Guinean Bichir and Smallmouth Bass Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 11, 2026
Possible with Caution

Keeping Guinean Bichir and Smallmouth Bass together is possible but requires caution due to mismatched flow preferences. Provide a spacious tank of at least 680 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Guinean Bichir

Polypterus ansorgii

Smallmouth Bass

Micropterus dolomieu

🐠Family Group
Guinean Bichir
Oddballs
Smallmouth Bass
Other
Temperament
Guinean Bichir
Semi-Aggressive (5/10)
Smallmouth Bass
Aggressive (7/10)
Temperature
✓ Compatible
Guinean Bichir
24–28°C
Smallmouth Bass
15–25°C
pH Range
✓ Compatible
Guinean Bichir
6.5–7.5
Smallmouth Bass
6.5–8
Hardness (dGH)
✓ Compatible
Guinean Bichir
5–15
Smallmouth Bass
5–20
Water Type
✓ Compatible
Guinean Bichir
Freshwater Only
Smallmouth Bass
Freshwater Only
Flow Preference
✗ No overlap
Guinean Bichir
Low
Smallmouth Bass
High
Min Tank Volume
Combined: 680 L
Guinean Bichir
680 L
Smallmouth Bass
680 L
Swimming Level
Shared: 1 zone
Guinean Bichir
Bottom
Smallmouth Bass
MiddleBottom
🏷️Behavior Tags
Guinean Bichir
Piscivore (Eats small/nano fish)Jumper (Lid Required)Nocturnal
Smallmouth Bass
Piscivore (Eats small/nano fish)Hyperactive / Fast SwimmerJumper (Lid Required)Territorial (Defends specific area)Generally AggressiveAggressive Eater (Starves shy fish)
Stocking calculator

Can your tank handle Guinean Bichir and Smallmouth Bass?

Compatibility is only part of the answer. Test both fish with your real tank size, current stock, and maintenance needs to see if you have enough space and a safe stocking level before you add them.

Guinean Bichir
Smallmouth Bass
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Behaviour & Temperament

Guinean Bichir is a moderately assertive species (5/10), while Smallmouth Bass is semi-aggressive (7/10). This modest difference means Smallmouth Bass may occasionally assert dominance over Guinean Bichir.

Guinean Bichir and Smallmouth Bass both frequent the Bottom (Substrate) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Worth noting: Guinean Bichir is nocturnal and will be most active after lights-out, naturally reducing daytime encounters. Also, Guinean Bichir is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: Provide a significantly larger tank (at least 50% more volume than the minimum) to allow both Guinean Bichir and Smallmouth Bass to establish separate territories. Add plenty of line-of-sight breaks using driftwood, rocks, and dense planting to reduce territorial confrontations.

Water Parameters

The safe temperature window for both species falls between 24°C and 25°C. Aim for the midpoint of this range (around 24.5°C) for optimal comfort.

Both fish can tolerate a pH between 6.5 and 7.5. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 5–15 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Guinean Bichir and Smallmouth Bass together, plan for an aquarium of at least 680 litres with a minimum length of 180 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Because this pairing requires extra vigilance, include plenty of hiding spots — caves, driftwood, and dense plant clusters — so the less dominant fish can retreat when needed.

Specific environmental needs for this combination include: Sand (Sifters), Smooth Gravel (Sensitive Barbels), Driftwood (Digestion/Hiding), Plants - Floating. Meeting these requirements will help both species thrive.

Guinean Bichir prefers Low (Still Water) flow while Smallmouth Bass needs High (River/Stream) flow. Consider positioning filter outlets and using baffles to create zones of different current intensity within the same tank.

Why This Pairing Needs Extra Planning in Practice

This pairing usually fails when the tank is treated like a standard mixed community and the caution flags are ignored. Guinean Bichir and Smallmouth Bass need extra room, more cover, and closer observation during the first few weeks so small aggression, feeding, or territory issues do not snowball into a long-term problem.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Guinean Bichir and Smallmouth Bass.

Frequently Asked Questions

Can Guinean Bichir and Smallmouth Bass live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 680 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Guinean Bichir and Smallmouth Bass need?

A minimum of 680 litres (tank length at least 180 cm) is recommended. This provides enough space for both species to establish their own areas and reduces the likelihood of territorial disputes.

What water temperature is best for Guinean Bichir and Smallmouth Bass together?

Keep the aquarium between 24°C and 25°C. A target of around 24.5°C sits comfortably within both species' preferred ranges.

Are Guinean Bichir or Smallmouth Bass aggressive?

Guinean Bichir is moderately assertive (5/10) and Smallmouth Bass is semi-aggressive (7/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Guinean Bichir and Smallmouth Bass need?

Both species overlap in the 6.5–7.5 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

How do I manage Smallmouth Bass's territorial behaviour?

Provide line-of-sight breaks using rocks, driftwood, and dense planting. A larger tank gives Smallmouth Bass space to claim a territory without encroaching on the other fish's area. Adding décor that divides the tank into distinct zones works especially well.

Does Guinean Bichir being nocturnal affect compatibility?

Guinean Bichir is most active after lights-out, which naturally reduces daytime encounters with its tank mate. This can actually be beneficial, as both fish get undisturbed time to feed and explore. Just ensure food reaches Guinean Bichir during evening hours.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
May 11, 2026
Last updated
May 11, 2026
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