Can Black-Banded Rainbowfish and Cardinal Tetra Live Together?

Possible with Caution

Keeping Black-Banded Rainbowfish and Cardinal Tetra together is possible but requires caution due to potential behavioral clashes. Provide a spacious tank of at least 100 litres with plenty of hiding spots to reduce stress. Monitor behaviour closely, especially during the first few weeks.


At a Glance

Black-Banded Rainbowfish

Melanotaenia nigrans

Cardinal Tetra

Paracheirodon axelrodi

🐠Family Group
Black-Banded Rainbowfish
Rainbowfish
Cardinal Tetra
Characins
Temperament
Black-Banded Rainbowfish
Peaceful (2/10)
Cardinal Tetra
Peaceful (1/10)
Temperature
✓ Compatible
Black-Banded Rainbowfish
22–28°C
Cardinal Tetra
24–29°C
pH Range
✓ Compatible
Black-Banded Rainbowfish
5.5–8
Cardinal Tetra
4–7
Hardness (dGH)
✓ Compatible
Black-Banded Rainbowfish
4–15
Cardinal Tetra
1–8
Water Type
✓ Compatible
Black-Banded Rainbowfish
Brackish Tolerant
Cardinal Tetra
Freshwater Only
Flow Preference
✓ Compatible
Black-Banded Rainbowfish
Moderate
Cardinal Tetra
Low
Min Tank Volume
Combined: 100 L
Black-Banded Rainbowfish
100 L
Cardinal Tetra
55 L
Swimming Level
Shared: 1 zone
Black-Banded Rainbowfish
TopMiddle
Cardinal Tetra
Middle
🏷️Behavior Tags
Black-Banded Rainbowfish
Hyperactive / Fast SwimmerJumper (Lid Required)
Cardinal Tetra
Nano / Bite-sized (Predation Risk)Hyperactive / Fast SwimmerShy / Slow Moving (Easily Stressed)
Stocking calculator

Can your tank handle Black-Banded Rainbowfish and Cardinal Tetra?

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.

Black-Banded Rainbowfish
Cardinal Tetra
Test both in my tank

Behaviour & Temperament

Black-Banded Rainbowfish is a peaceful species (2/10), while Cardinal Tetra is peaceful (1/10). This modest difference means Black-Banded Rainbowfish may occasionally assert dominance over Cardinal Tetra.

Black-Banded Rainbowfish and Cardinal Tetra both frequent the Middle (Open Water) region of the setup. This overlap can increase competition for space, so providing ample room and cover is important to keep both species comfortable.

Additional behavioural considerations to keep in mind: Hyperactive swimmers can stress shy, slow-moving species through constant motion.

Worth noting: Black-Banded Rainbowfish is a known jumper, so a tight-fitting lid is essential.

To improve the chances of a peaceful coexistence in this community tank: A larger aquarium with ample hiding spots can help diffuse aggression and give the less dominant fish space to retreat.

Water Parameters

The safe temperature window for both species falls between 24°C and 28°C. Aim for the midpoint of this range (around 26.0°C) for optimal comfort.

Both fish can tolerate a pH between 5.5 and 7. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 4–8 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Black-Banded Rainbowfish and Cardinal Tetra together, plan for an aquarium of at least 100 litres with a minimum length of 80 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: Plants - Densely covered, Leaf Litter/Blackwater, Driftwood (Digestion/Hiding). Meeting these requirements will help both species thrive.

Both species do well with moderate (standard) water movement, so a standard filtration setup rated for the tank volume should suffice.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Black-Banded Rainbowfish and Cardinal Tetra.

Show 12 more tank sizes

Frequently Asked Questions

Can Black-Banded Rainbowfish and Cardinal Tetra live together?

They can coexist, but the pairing requires careful monitoring. Provide ample space (at least 100 litres), plenty of hiding spots, and watch for signs of stress or aggression.

What size tank do Black-Banded Rainbowfish and Cardinal Tetra need?

A minimum of 100 litres (tank length at least 80 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 Black-Banded Rainbowfish and Cardinal Tetra together?

Keep the aquarium between 24°C and 28°C. A target of around 26.0°C sits comfortably within both species' preferred ranges.

Are Black-Banded Rainbowfish or Cardinal Tetra aggressive?

Black-Banded Rainbowfish is peaceful (2/10) and Cardinal Tetra is peaceful (1/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Black-Banded Rainbowfish and Cardinal Tetra need?

Both species overlap in the 5.5–7 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.


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