Can Blind Cave Tetra and Boeseman's Rainbowfish Live Together?

Reviewed by Guidarium Editorial DeskUpdated April 28, 2026
Not Recommended

Blind Cave Tetra and Boeseman's Rainbowfish are not recommended as tank mates due to no temperature overlap. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Blind Cave Tetra

Astyanax mexicanus

Boeseman's Rainbowfish

Melanotaenia boesemani

🐠Family Group
Blind Cave Tetra
Characins
Boeseman's Rainbowfish
Rainbowfish
Temperament
Blind Cave Tetra
Mostly Peaceful (4/10)
Boeseman's Rainbowfish
Peaceful (2/10)
Temperature
✗ No overlap
Blind Cave Tetra
20–25°C
Boeseman's Rainbowfish
26–30°C
pH Range
✓ Compatible
Blind Cave Tetra
6.5–8
Boeseman's Rainbowfish
7–8.1
Hardness (dGH)
✓ Compatible
Blind Cave Tetra
8–20
Boeseman's Rainbowfish
9–19
Water Type
✓ Compatible
Blind Cave Tetra
Freshwater Only
Boeseman's Rainbowfish
Freshwater Only
Flow Preference
✓ Compatible
Blind Cave Tetra
Moderate
Boeseman's Rainbowfish
Moderate
Min Tank Volume
Combined: 200 L
Blind Cave Tetra
110 L
Boeseman's Rainbowfish
200 L
Swimming Level
Shared: 1 zone
Blind Cave Tetra
MiddleBottom
Boeseman's Rainbowfish
TopMiddle
🏷️Behavior Tags
Blind Cave Tetra
Hyperactive / Fast SwimmerFin NipperAggressive Eater (Starves shy fish)
Boeseman's Rainbowfish
Hyperactive / Fast SwimmerAggressive Eater (Starves shy fish)Jumper (Lid Required)
Stocking calculator

Can your tank handle Blind Cave Tetra and Boeseman's Rainbowfish?

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.

Blind Cave Tetra
Boeseman's Rainbowfish
Test both in my tank

Behaviour & Temperament

Blind Cave Tetra is a generally mild-mannered species (4/10), while Boeseman's Rainbowfish is peaceful (2/10). This modest difference means Blind Cave Tetra may occasionally assert dominance over Boeseman's Rainbowfish.

Blind Cave Tetra and Boeseman's Rainbowfish 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.

Worth noting: Boeseman's Rainbowfish is a known jumper, so a tight-fitting lid is essential.

Water Parameters

There is no temperature overlap between Blind Cave Tetra (20–25°C) and Boeseman's Rainbowfish (26–30°C). This fundamental mismatch makes long-term cohabitation impractical.

Both fish can tolerate a pH between 7 and 8. Maintaining a stable value within this band is more important than hitting an exact number.

For general hardness, the shared comfort zone is 9–19 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Blind Cave Tetra and Boeseman's Rainbowfish together, plan for an aquarium of at least 200 litres with a minimum length of 120 cm. This recommendation combines the stricter species minimums with a community-load allowance so the pairing has realistic long-term space and filtration headroom.

Providing a mix of open swimming space and sheltered areas with rocks, driftwood, or plants will keep both species comfortable and allow natural behaviour.

Specific environmental needs for this combination include: Smooth Gravel (Sensitive Barbels), Plants - lighly covered. 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.

Why This Pairing Usually Fails in Practice

Blind Cave Tetra and Boeseman's Rainbowfish are the kind of pair that can look acceptable in a shop but become a maintenance problem at home. The main risk is not a single number in the chart; it is the way incompatible behavior, water needs, or pressure on space compounds over time once both fish are established in the same tank.

Suitable Tank Sizes

Standard aquarium sizes large enough for both Blind Cave Tetra and Boeseman's Rainbowfish.

Show 5 more tank sizes

Frequently Asked Questions

Can Blind Cave Tetra and Boeseman's Rainbowfish live together?

No. This combination is not recommended. Key incompatibilities — such as non-overlapping temperature ranges — make cohabitation unsafe.

What size tank do Blind Cave Tetra and Boeseman's Rainbowfish need?

A minimum of 200 litres (tank length at least 120 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 Blind Cave Tetra and Boeseman's Rainbowfish together?

Unfortunately, there is no temperature range that satisfies both species. Blind Cave Tetra requires 20–25°C, while Boeseman's Rainbowfish needs 26–30°C.

Are Blind Cave Tetra or Boeseman's Rainbowfish aggressive?

Blind Cave Tetra is generally mild-mannered (4/10) and Boeseman's Rainbowfish is peaceful (2/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Blind Cave Tetra and Boeseman's Rainbowfish need?

Both species overlap in the 7–8 pH range. Consistency is key — avoid sudden swings, and test regularly to stay within this window.

Will Blind Cave Tetra nip Boeseman's Rainbowfish's fins?

Blind Cave Tetra is a known fin nipper. If Boeseman's Rainbowfish has long or flowing fins, there is a real risk of fin damage. Keeping Blind Cave Tetra in a larger group can help redirect nipping behaviour toward conspecifics.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
April 28, 2026
Last updated
April 28, 2026
Issues or corrections?
Contact the editorial team

Related Comparisons