Celestial pearl danio

Identity and search names

Single-species profile for Danio margaritatus, formerly sold as galaxy rasbora. Do not confuse it with superficially similar Danio or Microrasbora species. Search names: galaxy rasbora, CPD

Environment and housing

Dense fine-leaved planting, moss, shaded margins, open feeding lanes, gentle filtration and a secure lid

Feeding and nutrition

Feeding ecology: Micropredatory omnivore taking tiny crustaceans, insect larvae and finely sized prepared foods

Feeding routine: Offer small varied foods once or twice daily at several points so subordinate fish eat

Breeding and reproduction

Continuous egg scatterer among moss or fine plants; adults may eat eggs and fry

Parental care: No parental care; remove eggs or provide dense cover for fry survival

System demands

Filtration: Use mature biological filtration sized for the adult stock and feeding load, with guarded intakes and a flow pattern the species can use without continual effort.

Aeration: Maintain strong gas exchange and stable dissolved oxygen, especially overnight, during warm weather, medication, crowding or any interruption to filtration.

Maintenance: Test ammonia and nitrite after changes or abnormal behaviour; remove waste from the occupied zone and perform regular water changes matched to temperature and mineral chemistry.

Detailed husbandry

Identity scope

Single-species profile for Danio margaritatus, formerly sold as galaxy rasbora. Do not confuse it with superficially similar Danio or Microrasbora species.

Adult size and space

Up to about 2.1 cm standard length. At least 60 L for a group of ten or more, with multiple feeding and retreat areas. Adult dimensions, activity, social structure and waste production matter more than sale size.

Social structure

Keep at least ten; use dense cover and a female-biased group where possible

Swimming zone

Primary zone: Middle and lower water. Keep that zone usable and provide unobstructed feeding access, movement and refuge appropriate to the species.

Feeding ecology

Micropredatory omnivore taking tiny crustaceans, insect larvae and finely sized prepared foods

Feeding plan

Offer small varied foods once or twice daily at several points so subordinate fish eat

Water stability

Maintain 20–26 °C; pH: 6.0–7.8; hardness/minerals: Soft to moderately hard. Stable temperature, oxygen, mineral chemistry and nitrogen-cycle control matter more than chasing a single exact number.

Habitat structure

Dense fine-leaved planting, moss, shaded margins, open feeding lanes, gentle filtration and a secure lid

Compatibility plan

Use tiny peaceful species with similar temperature needs and feeding speed; avoid large, boisterous or predatory tankmates

Breeding plan

Continuous egg scatterer among moss or fine plants; adults may eat eggs and fry. Parental care: No parental care; remove eggs or provide dense cover for fry survival. Do not trigger reproduction without capacity for aggression, eggs or fry and lawful long-term placement.

Quarantine

Quarantine new fish in a separate cycled aquarium with dedicated nets, containers and siphons. Match temperature and mineral chemistry gradually, confirm normal feeding, respiration, skin, fins and waste, and never pour transport water into the established aquarium.

Welfare checks

Check individual abdominal fullness, male sparring, colour, fin damage, group distribution and whether every fish enters feeding lanes.

Biosecurity and release

Never release fish, eggs, fry, aquarium water, sediment, plants or foods into drains, dams or natural waterways. Check the exact accepted identity in current BICON, Australian live-fish import requirements and applicable South Australian rules before import, sale or movement; import eligibility does not authorise release or wild collection.

Main risk

Dense planting can conceal chronic bullying or starvation. Check individual body condition rather than assuming a hidden fish is merely shy.

Adult Projected Load

Moderate for the planned adult stock. Calculate filtration, oxygen and swimming space from the full adult size (Up to about 2.1 cm standard length) and social group (Keep at least ten; use dense cover and a female-biased group where possible), not the juvenile sale size.

Filtration

Use mature mechanical and biological filtration with protected intakes and enough turnover for the adult group while preserving species-appropriate current and refuge.

Aeration

Provide strong gas exchange and backup aeration; increase oxygen support before warm weather, heavy feeding, crowding, medication or filter interruption reduces the safety margin.

Maintenance

Remove uneaten food and bottom waste, clean prefilters before flow falls, test ammonia and nitrite after changes, and perform regular temperature- and chemistry-matched water changes.

Overridable Warnings

Dense planting can conceal chronic bullying or starvation. Check individual body condition rather than assuming a hidden fish is merely shy.

Welfare and risk

Check individual abdominal fullness, male sparring, colour, fin damage, group distribution and whether every fish enters feeding lanes.

Sources

• Eschmeyer’s Catalog of Fishes — Danio margaritatus — Accepted name, synonym and taxonomic placement
• Australian Government — Danio margaritatus assessment report — Identity, adult size, native habitat, biology and Australian risk assessment
• IUCN Red List search — Danio margaritatus — Conservation and provenance cross-check
• Australian Government — importing live ornamental fish — Australian import pathway and biosecurity requirements
• PIRSA — South Australian noxious fish list — South Australian possession, trade and release context
• Eschmeyer’s Catalog of Fishes current search — Danio margaritatus — Current accepted-name, synonym, distribution and habitat cross-check