Axelrod's Rainbowfish

Chilatherina axelrodi

Rainbowfish
Reviewed by Guidarium Editorial DeskUpdated April 29, 2026

A highly active, colorful schooling fish native to Papua New Guinea. Known for a bluish-grey upper body and yellowish-white lower body divided by a dark lateral stripe. Like most rainbowfish, they are incredibly fast, active swimmers that require pristine water, moderate flow, and significant horizontal swimming space.

Axelrod's Rainbowfish At a Glance

Adult Size10 cm
Body ShapeCompressed
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceModerate
Waste OutputLow
StockingSchool of 6+

Axelrod's Rainbowfish Tank Requirements

Minimum Volume150 L
Minimum Length120 cm
FlowModerate
Water TypeFreshwater Only
Must-Haves in the Tank
Plants - Densely covered
Stocking calculator

Will Axelrod's Rainbowfish fit in your tank?

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

Axelrod's Rainbowfish
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Axelrod's Rainbowfish Water Parameters

Temperature2430°C
pH78.5
Hardness618 dGH

Axelrod'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)

Axelrod's Rainbowfish Varieties

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

Male

Males are slightly larger, noticeably deeper-bodied as they mature, and exhibit much brighter colors, especially during morning spawning displays. They may harmlessly spar with other males for dominance.

Differs in 1 trait from base species

Also known as: Male Axelrod, Standard

TemperamentMostly Peaceful

Female

Females are slightly smaller, more streamlined, and have subdued, silvery-yellow coloration. Keeping a ratio of more females than males is recommended to reduce harassment during breeding behavior.

Differs in 2 traits from base species

Also known as: Female Axelrod

Adult Size8.5 cm
TemperamentPeaceful

Axelrod's Rainbowfish Care Guide Summary

The Axelrod's Rainbowfish, scientifically known as Chilatherina axelrodi, belongs to the Rainbowfish family group. Adults reach a maximum size of approximately 10 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 low level of biological waste.

To thrive, the Axelrod's Rainbowfish requires a freshwater only aquarium with a minimum volume of 150 litres and a tank length of at least 120 cm. Water temperature should be maintained between 24°C and 30°C, with a pH range of 78.5 and a general hardness of 618 dGH. A moderate water flow is preferred.

The Axelrod'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.

Axelrod's Rainbowfish Habitat Setup

When setting up an aquarium for the Axelrod'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 dense planting to provide cover, break sightlines, and reduce stress. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.

Axelrod's Rainbowfish Compatibility Notes

Classified as peaceful, the Axelrod'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 Axelrod's Rainbowfish Is Actually For

Axelrod'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 Axelrod'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.

Axelrod's Rainbowfish Recommended Tank Sizes

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

Show 5 more tank sizes

Frequently Asked Questions About Axelrod's Rainbowfish

How big does Axelrod's Rainbowfish get?

Axelrod's Rainbowfish (Chilatherina axelrodi) typically reaches a maximum adult size of approximately 10 cm. They have a compressed body shape and a moderate growth rate.

What tank size does Axelrod's Rainbowfish need?

A minimum aquarium volume of 150 litres and a tank length of at least 120 cm are recommended for Axelrod's Rainbowfish. This ensures enough swimming space and helps maintain stable water conditions.

What water parameters does Axelrod's Rainbowfish need?

Axelrod's Rainbowfish thrives in freshwater only conditions with a temperature range of 24–30°C, a pH between 7 and 8.5, and a general hardness of 6–18 dGH. A moderate water flow is preferred.

Is Axelrod's Rainbowfish peaceful or aggressive?

Axelrod'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 Axelrod's Rainbowfish should be kept together?

Axelrod'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 Axelrod's Rainbowfish have any special tank requirements?

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

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

Yes. Axelrod'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
April 29, 2026
Last updated
April 29, 2026
Issues or corrections?
Contact the editorial team

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