Celestial Pearl Danio (Galaxy Rasbora)

Danio margaritatus

Cyprinids

A breathtaking nano fish native to small, vegetated ponds in Myanmar. They feature a midnight blue body covered in pearlescent spots with striking red and black striped fins. CPDs are notoriously shy and require heavily planted aquariums to feel secure. Males will constantly display and mock-spar with each other, so a larger group is essential to disperse this behavior.

At a Glance

Adult Size2.5 cm
Body ShapeFusiform
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceLow
Waste OutputLow
StockingSchool of 6+

Tank Requirements

Minimum Volume38 L
Minimum Length45 cm
FlowLow
Water TypeFreshwater Only
Must-Haves in the Tank
Plants - Densely covered

Water Parameters

Temperature2026°C
pH6.57.5
Hardness515 dGH

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
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)

Available Varieties

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

Standard

The standard form found in the aquarium trade. Usually sold unsexed. Best kept in groups of 6 or more, ideally with a higher ratio of females to males to reduce stress from male sparring. Ensure dense planting to overcome their natural shyness.

Differs in 1 trait from base species

Also known as: Unsexed, Schooling

Behavior Traits
Nano / Bite-sized (Predation Risk)Shy / Slow Moving (Easily Stressed)

Celestial Pearl Danio (Galaxy Rasbora) Care Guide Summary

The Celestial Pearl Danio (Galaxy Rasbora), scientifically known as Danio margaritatus, belongs to the Cyprinids family group. Adults reach a maximum size of approximately 2.5 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a low level of biological waste.

To thrive, the Celestial Pearl Danio (Galaxy Rasbora) requires a freshwater only aquarium with a minimum volume of 38 litres and a tank length of at least 45 cm. Water temperature should be maintained between 20°C and 26°C, with a pH range of 6.57.5 and a general hardness of 515 dGH. A low water flow is preferred.

The Celestial Pearl Danio (Galaxy Rasbora) is a rewarding species to keep, provided its core environmental needs are met. The Celestial Pearl Danio (Galaxy Rasbora) is typically available in one standard form.

Celestial Pearl Danio (Galaxy Rasbora) Habitat Setup

When setting up an aquarium for the Celestial Pearl Danio (Galaxy Rasbora), a low water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include dense planting to provide cover, break sightlines, and reduce stress.

Celestial Pearl Danio (Galaxy Rasbora) Compatibility Notes

Classified as peaceful, the Celestial Pearl Danio (Galaxy Rasbora) 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, boisterous or fast-moving tankmates may cause this species undue stress. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.

Frequently Asked Questions About Celestial Pearl Danio (Galaxy Rasbora)

How big does Celestial Pearl Danio (Galaxy Rasbora) get?+
Celestial Pearl Danio (Galaxy Rasbora) (Danio margaritatus) typically reaches a maximum adult size of approximately 2.5 cm. They have a fusiform body shape and a moderate growth rate.
What tank size does Celestial Pearl Danio (Galaxy Rasbora) need?+
A minimum aquarium volume of 38 litres and a tank length of at least 45 cm are recommended for Celestial Pearl Danio (Galaxy Rasbora). This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Celestial Pearl Danio (Galaxy Rasbora) need?+
Celestial Pearl Danio (Galaxy Rasbora) thrives in freshwater only conditions with a temperature range of 20–26°C, a pH between 6.5 and 7.5, and a general hardness of 5–15 dGH. A low water flow is preferred.
Is Celestial Pearl Danio (Galaxy Rasbora) peaceful or aggressive?+
Celestial Pearl Danio (Galaxy Rasbora) is classified as peaceful with an aggression score of 2 out of 10. They are generally well-suited to peaceful community tanks.
How many Celestial Pearl Danio (Galaxy Rasbora) should be kept together?+
Celestial Pearl Danio (Galaxy Rasbora) 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 Celestial Pearl Danio (Galaxy Rasbora) have any special tank requirements?+
Yes. Celestial Pearl Danio (Galaxy Rasbora) benefits from plants - densely covered in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

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