Rasboras, danios & minnows · Danio margaritatus

Celestial pearl danio care guide

Also called: Galaxy rasbora, CPD

A tiny spotted nano fish from Myanmar, also sold as the galaxy rasbora. Males turn deep blue with red-orange fins. They are shy, so keep eight or more in a densely planted tank with small, calm tankmates and tiny foods.

Celestial pearl danios need a tank of at least 10 gallons (38 L), a group of 8 or more, and water at 20–25°C (68–77°F) with a pH of 6.5–7.8. They grow to about 2.5 cm (1 in) and are peaceful.

Plan a tank with celestial pearl daniosSee all tank mates

Celestial pearl danio quick facts

Scientific nameDanio margaritatus
FamilyDanionidae
OriginSalween basin, Shan State, Myanmar and nearby northern Thailand (now widely captive-bred)
Adult size2.5 cm (1 in)
Minimum tank10 gallons (38 L)
Temperature20–25°C (68–77°F)
pH6.5–7.8
Hardness (GH)5–15 dGH
Group size8 or more (shoaling fish)
TemperamentPeaceful
Swims atMiddle
DietOmnivore
Care levelModerate
Lifespan3–5 years
Safe with shrimp?Mostly (eats baby shrimp)
Safe with plants?Yes

Tank setup

A 10-gallon (38 L) tank works for a small group, but 20 gallons (76 L) or more lets you keep the bigger group they prefer. Plant it heavily, add floating plants and use a dark substrate so they feel safe. Gentle filtration, such as a sponge filter, suits them better than strong flow.

How many celestial pearl danios in a tank?

The smallest common tank that suits celestial pearl danios is a 10 gallon. Here is roughly how many fit in each size when they are the only fish, based on adult size and waste output. Leave room if you want tank mates.

TankCelestial pearl danios (alone)
3 gallonToo small
5 gallonToo small
10 gallon8–27
15 gallon8–41
20 gallon8–55
20 gallon long8–55
29 gallon8–79
40 gallon8–110
55 gallon8–151
75 gallon8–206
125 gallon8–344

What you need for celestial pearl danios

Sized for a 10 gallon tank, the smallest common size that suits a group of 8 celestial pearl danios. For a different tank or a mix of fish, use the stocking calculator for a list sized to your plan.

Tank and equipment

Food and extras for celestial pearl danios

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Water parameters

Aim for about 20–25 °C (68–77 °F), pH 6.5–7.8 and soft to moderately hard water. In the wild they live in clear, shallow, plant-choked pools, so stable, clean water matters more than exact numbers. Don't let the tank run hot for long periods.

Best tank mates for celestial pearl danios

These popular species share celestial pearl danios' water needs and temperament. See the full list of 70 good matches.

Avoid keeping celestial pearl danios with

  • Angelfish: Angelfish can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.
  • Common goldfish: Common goldfish can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.
  • Fancy goldfish: Fancy goldfish can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.
  • Oscar: Oscar can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.
  • Bala shark: Bala shark can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.
  • Blood parrot cichlid: Blood parrot cichlid can eat celestial pearl danios: they're small enough to fit in its mouth once it's grown.

Feeding

They have very small mouths. Offer crushed flakes, micro pellets and small frozen or live foods such as baby brine shrimp, daphnia and cyclops. They rarely feed at the surface, so use slow-sinking foods and feed small amounts more than once a day if you can.

Behavior

Peaceful but timid, and they hide if kept with big or boisterous fish. Males spar all day by flaring and circling each other. In a roomy, densely planted tank with more females than males this is mostly display, but in small or bare tanks a dominant male can chase weaker males until they die. Torn fins within the group are common, yet they seldom bother other species.

Breeding

A well-fed group spawns often, with females scattering small batches of eggs among fine plants or moss. Adults eat any eggs they find. For more fry, move the moss or a spawning mop with eggs to a separate container. Eggs hatch in about three days, and the fry need very fine foods like infusoria before baby brine shrimp.

Tips from experienced keepers

  • Buy a group of eight or more. In small groups they stay hidden and you rarely see them.
  • Plant densely and add floating plants. More cover makes them bolder, not shyer.
  • Use tiny foods: crushed flakes, micro pellets and frozen baby brine shrimp or cyclops.
  • Pair them with other tiny, calm fish such as glowlight danios, pygmy corydoras or small rasboras.
  • Adult cherry shrimp are usually safe, but expect some baby shrimp to be eaten.

Frequently asked questions

Is the celestial pearl danio a rasbora?

No. It was first sold as the galaxy rasbora after its discovery in 2006, but it is a true danio, Danio margaritatus. The old name is still common in shops.

How many celestial pearl danios should be kept together?

Keep at least eight. Groups of 10 to 20 are even better, because the fish become bolder and more colourful and male sparring is spread out.

Can celestial pearl danios live with shrimp?

Yes, they are a popular choice for shrimp tanks. They usually leave adult dwarf shrimp alone but will eat tiny shrimplets, so add plenty of moss for cover.

Sources

We checked these references when writing this page. Values are for healthy long-term keeping, not survival limits. Last reviewed 2026-10-13. See our editorial policy.