Can Bleher's Rainbowfish and Green Neon Tetra Live Together?

Reviewed by Guidarium Editorial DeskUpdated May 6, 2026
Not Recommended

Bleher's Rainbowfish and Green Neon Tetra are not recommended as tank mates due to conflicting pH requirements. Housing these species together is likely to result in stress, health problems, or direct harm to one or both fish.


At a Glance

Bleher's Rainbowfish

Chilatherina bleheri

Green Neon Tetra

Paracheirodon simulans

🐠Family Group
Bleher's Rainbowfish
Rainbowfish
Green Neon Tetra
Characins
Temperament
Bleher's Rainbowfish
Peaceful (2/10)
Green Neon Tetra
Peaceful (0/10)
Temperature
✓ Compatible
Bleher's Rainbowfish
24–29°C
Green Neon Tetra
24–29°C
pH Range
✗ No overlap
Bleher's Rainbowfish
7–8
Green Neon Tetra
4.5–6.5
Hardness (dGH)
✓ Compatible
Bleher's Rainbowfish
5–15
Green Neon Tetra
1–8
Water Type
✓ Compatible
Bleher's Rainbowfish
Freshwater Only
Green Neon Tetra
Freshwater Only
Flow Preference
✓ Compatible
Bleher's Rainbowfish
Moderate
Green Neon Tetra
Low
Min Tank Volume
Combined: 200 L
Bleher's Rainbowfish
200 L
Green Neon Tetra
38 L
Swimming Level
Shared: 1 zone
Bleher's Rainbowfish
TopMiddle
Green Neon Tetra
Middle
🏷️Behavior Tags
Bleher's Rainbowfish
Hyperactive / Fast SwimmerJumper (Lid Required)
Green Neon Tetra
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)
Stocking calculator

Can your tank handle Bleher's Rainbowfish and Green Neon 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.

Bleher's Rainbowfish
Green Neon Tetra
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Behaviour & Temperament

Bleher's Rainbowfish is a peaceful species (2/10), while Green Neon Tetra is peaceful (0/10). This modest difference means Bleher's Rainbowfish may occasionally assert dominance over Green Neon Tetra.

Bleher's Rainbowfish and Green Neon 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: Bleher's Rainbowfish is a known jumper, so a tight-fitting lid is essential.

Water Parameters

The safe temperature window for both species falls between 24°C and 29°C. Aim for the midpoint of this range (around 26.5°C) for optimal comfort.

The pH requirements of Bleher's Rainbowfish (7–8) and Green Neon Tetra (4.5–6.5) do not overlap, making it impossible to satisfy both species simultaneously.

For general hardness, the shared comfort zone is 5–8 dGH. Regular testing will ensure conditions stay within this range.

Tank Setup

To house Bleher's Rainbowfish and Green Neon Tetra 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: Plants - lighly covered, Leaf Litter/Blackwater, Plants - Densely covered, Plants - Floating. 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

Bleher's Rainbowfish and Green Neon Tetra 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 Bleher's Rainbowfish and Green Neon Tetra.

Show 5 more tank sizes

Frequently Asked Questions

Can Bleher's Rainbowfish and Green Neon Tetra live together?

No. This combination is not recommended. Key incompatibilities — such as critical behavioural conflicts — make cohabitation unsafe.

What size tank do Bleher's Rainbowfish and Green Neon Tetra 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 Bleher's Rainbowfish and Green Neon Tetra together?

Keep the aquarium between 24°C and 29°C. A target of around 26.5°C sits comfortably within both species' preferred ranges.

Are Bleher's Rainbowfish or Green Neon Tetra aggressive?

Bleher's Rainbowfish is peaceful (2/10) and Green Neon Tetra is peaceful (0/10). Their similar temperaments generally lead to a peaceful coexistence.

What pH do Bleher's Rainbowfish and Green Neon Tetra need?

Their pH requirements do not overlap. Bleher's Rainbowfish prefers 7–8, while Green Neon Tetra needs 4.5–6.5. This makes them incompatible in the same water chemistry.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
May 6, 2026
Last updated
May 6, 2026
Issues or corrections?
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