Bleher's Rainbowfish

Chilatherina bleheri

Rainbowfish
Reviewed by Guidarium Editorial DeskUpdated May 2, 2026

A stunning, highly active schooling fish endemic to Lake Holmes (Danau Bira) in Papua, Indonesia. Known for its distinct dual-coloration, with the front half being greenish-blue and the back half turning a vibrant red/orange. They are famously active darters and require long tanks with significant open swimming space and well-oxygenated water.

Bleher's Rainbowfish At a Glance

Adult Size12 cm
Body ShapeCompressed
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputMedium
StockingSchool of 6+

Bleher's Rainbowfish Tank Requirements

Minimum Volume200 L
Minimum Length120 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Plants - lighly covered
Stocking calculator

Will Bleher's Rainbowfish fit in your tank?

Care guides tell you what Bleher's Rainbowfish needs, the next question is whether your tank can safely provide it. Test Bleher's Rainbowfish against your tank size, maintenance needs, and the fish you already keep before you buy.

Bleher's Rainbowfish
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Bleher's Rainbowfish Water Parameters

Temperature2429°C
pH78
Hardness515 dGH

Bleher's Rainbowfish Temperament & Compatibility

Aggression LevelPeaceful
2/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least6 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerJumper (Lid Required)

Bleher's Rainbowfish Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Male

Males are slightly larger, deeper-bodied, and display the spectacular intense red/orange posterior coloration, especially during morning spawning displays. They frequently spar harmlessly with other males to establish hierarchy.

Differs in 3 traits from base species

Also known as: Show Male, Adult Male

Adult Size12 cm
TemperamentMostly Peaceful
Behavior Traits
Hyperactive / Fast SwimmerJumper (Lid Required)Aggressive to same species/look-alikes

Female

Females are slightly smaller, more slender, and display a subdued, overall silvery-greenish hue. They are essential to keeping a balanced shoal (recommend a 1:1 or 1:2 male to female ratio) to disperse male attention.

Differs in 2 traits from base species

Also known as: Female

Adult Size10 cm
TemperamentPeaceful

Bleher's Rainbowfish Care Guide Summary

The Bleher's Rainbowfish, scientifically known as Chilatherina bleheri, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 12 cm and have a compressed body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a medium level of biological waste.

To thrive, the Bleher's Rainbowfish requires a freshwater only aquarium with a minimum volume of 200 litres and a tank length of at least 120 cm. Water temperature should be maintained between 24°C and 29°C, with a pH range of 78 and a general hardness of 515 dGH. A moderate water flow is preferred.

The Bleher's Rainbowfish is a rewarding species to keep, provided its core environmental needs are met. This species is available in 2 varieties: Male and Female. Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Bleher's Rainbowfish Habitat Setup

When setting up an aquarium for the Bleher's Rainbowfish, a moderate water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include light plant coverage for partial shade. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.

Bleher's Rainbowfish Compatibility Notes

Classified as peaceful, the Bleher's Rainbowfish is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. When choosing tankmates, their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.

Who Bleher's Rainbowfish Is Actually For

Bleher's Rainbowfish is best for a fishkeeper who wants a species that can settle into a calmer community setup and can provide a keeper who can commit to a proper group of at least 6. It makes the most sense for a hobbyist who will actually build around its needs, especially plants.

The most common mistake is buying Bleher's Rainbowfish for looks first and only later discovering how its adult size, behavior, or bioload changes the whole tank plan. Another frequent problem is underestimating its social needs. A token pair or trio often behaves very differently from a real group.

Bleher's Rainbowfish Recommended Tank Sizes

Standard aquarium sizes that meet the minimum volume and length requirements for Bleher's Rainbowfish.

Show 5 more tank sizes

Frequently Asked Questions About Bleher's Rainbowfish

How big does Bleher's Rainbowfish get?

Bleher's Rainbowfish (Chilatherina bleheri) typically reaches a maximum adult size of approximately 12 cm. They have a compressed body shape and a moderate growth rate.

What tank size does Bleher's Rainbowfish need?

A minimum aquarium volume of 200 litres and a tank length of at least 120 cm are recommended for Bleher's Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.

What water parameters does Bleher's Rainbowfish need?

Bleher's Rainbowfish thrives in freshwater only conditions with a temperature range of 24–29°C, a pH between 7 and 8, and a general hardness of 5–15 dGH. A moderate water flow is preferred.

Is Bleher's Rainbowfish peaceful or aggressive?

Bleher's Rainbowfish is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.

How many Bleher's Rainbowfish should be kept together?

Bleher's Rainbowfish is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.

Does Bleher's Rainbowfish have any special tank requirements?

Yes. Bleher's Rainbowfish benefits from plants - lighly covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Does Bleher's Rainbowfish need a lid on the tank?

Yes. Bleher's Rainbowfish is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.

Editorial Review

Guidarium Editorial Desk

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

Last reviewed
May 2, 2026
Last updated
May 2, 2026
Issues or corrections?
Contact the editorial team

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