Freshwater Fish

Celestial Pearl Danio Care: Tank Setup, Breeding, Tank Mates And Size

Bright, colorful, and attractive, the Celestial Pearl Danio (aka Galaxy Rasbora) is a stunner, adding pops of color and life to an aquarium. They’re beautiful freshwater fishes that are relatively easy to keep. To make your CPDs happy, though, consider proper celestial pearl danio care.

These stunning species are popular in the fishkeeping world. Even beginners who have just gotten into the hobby find it rewarding to stock their tank with these little beauties.

In this guide, you’ll learn about the ways to take care of your danios, including their food and diet, tank setup, and so much more.

Understanding Celestial Pearl Danios

Celestial pearl danio care is quite straightforward and simple, making these danios some of the most favorites among fish keepers looking to add color and life to their aquarium.

The celestial pearl danio (former scientific name: Celestichthys margaritatus) is versatile and adaptable to a lot of situations, like temperature requirements (more about this later).

But before buying your danios, it pays off to understand them first.  This will help you decide if they’re the right pet fish for you or not.

The scientific name of the miniature cyprinid, or the pearl danios, literally means “heavenly fish adorned with pearls.” 

However, they were later reclassified as danio, so they’re renamed Danio margaritatus (reclassified scientific name).

These cuties are known under several names – celestial pearl danio, galaxy rasbora, Celestichthys margaritatus, Microrasbora sp. ‘galaxy,’ and Danio margaritatus,

Galaxy Rasbora is perhaps their most popular name in the fishkeeping hobby.  This name was given by those who brought the celestial pearl danio to the market. 

The small size of the celestial pearl was the reason it was mistakenly thought to be under the species of rasbora. This common name is still used even though the fish was reclassified.

Danio margaritatus is commonly distributed from Northern Thailand and Myanmar and requires an omnivore diet.

These danios can grow from 0.75 to 1 inch and have a life expectancy between 3 to 5 years.  Their usual colors are dark blue with yellow or white spots in a galaxy pattern, hence their common name galaxy rasbora.

They require a minimum tank size of 10 gallons and temperatures ranging from 71 to 78 degrees Fahrenheit, pH level of 6.5 to 7.5, and water hardness of 1-5 dGH. 

These species have a peaceful temperament and moderate care level requirements.

Behavior And Temperament

Celestial Pearl Danios are calm and peaceful, which make them an ideal addition to any tank with peaceful species.

Typically, they’re sold in packs of 8 and 10. It is because these species tend to group up and swim with their group.

They love exploring the tank, so it is advisable to have a well-planted one.

For the longest time, we used to believe that these danios are shoaling fish.  However, they’re not real shoaling fishes.

Once they become familiar with their new environment, they love doing things on their own and live independently. So even if they love spending time with their group, they’ll eventually live separately from the rest once they feel comfortable.

It is important to consider their temperament to ensure harmonious living of all the species in your tank.  Remember that the male pearl danios tend to compete with other males for the attention of the female.

That’s why you must clearly identify which the males and females are.  You should not put a lot of male danios in your tank.

Otherwise, males will constantly fight over females. This can lead to injuries and fatalities.

I recommend that you keep more females than males in your tank in order to minimize the competition and fights among males.

When it comes to their behavior, they tend to stay at the tank’s bottom. They hide and explore among the aquatic plants and rocks.  They swim to the middle and top layers of the tank when it’s feeding time. 

Generally, these species are timid and shy so they stay near the tank’s bottom. You might think that they’re lonely or stressed, but it is their nature to act this way.

Provided you keep their tank clean with optimal water conditions, you can be sure that they will thrive and live happily.

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Overall, celestial pearl danios are peaceful species provided you keep more females than males in one tank. They also tend to shoal as they become familiar with their new home. Know of these things for proper celestial pearl danio care.

Size And Lifespan

To understand the fish further and help you decide whether the celestial pearl is for you or not, let’s now talk about its size and lifespan.

A full-grown adult can reach between 0.75 and1 inches in length.  They also have quite a long lifespan from three to five years depending on the level of care when in captivity.

Appearance And Gender Differences

They have blue bodies unique for their reddish fins and pearly dots resembling a galaxy, hence their common name galaxy rasbora. 

These fishes are known to possess a fusiform and narrow body. They also have large fins.

However, males can be brighter and thinner. Often, they do have a noticeably deep blue body and lovely pearl-like spot on their flanks.   Sometimes, the dots are arranged in a galaxy pattern or rows.

Male celestial pearl danios also possess a red stripe, which is lined with black running through the center of the fish’s translucent dorsal fin. You’ll also notice their red belly, while the dominant male CPDs typically have a red stripe on the back.

Meanwhile, the females are less bright than the males and have only fewer pearly dots.  You can also easily distinguish them with their orange fins and translucent anal fin instead of red pelvic, caudal, and dorsal fins.

Sometimes, there are female celestial pearl danios with an orange belly or golden belly.

If you’re breeding celestial pearl danios, you should notice that they develop a black spot in the front section of their caudal fin when they’re ready to spawn.  This area of their body also becomes plump.

Celestial Pearl Danio Care And Maintenance

These danios are easy to care for and maintain, making them suitable for beginner aquarists.  They don’t need a large tank to live and thrive. It will suffice to house them in a 10-gallon tank with up to 10 fishes.

But while they are not demanding species, they do need a well-planted tank because they love exploring and hiding among the plants.  

They are quite flexible and don’t need a heater.  You can keep them in temperatures from low to middle 70 degrees Fahrenheit.  

They can tolerate a low temperature like 65 degrees Fahrenheit to a high temperature of up to 80 degrees Fahrenheit. 

However, it would be best to keep them within their required temperature range, allowing them to live comfortably and happily.

When the water’s temperature fluctuates and drops to 70 degrees Fahrenheit, it would be wise to use a heater with a built-in thermostat.

To keep them healthy, it is essential to keep them in a cycled tank, which parameters should be ideally with >0 ppm nitrate, 0 ppm nitrite, and 0 ppm ammonia.

But even if a cycled tank will produce nitrates, it must be only under 20 ppm to prevent a poor water quality.

Tank Setup

It is crucial to set up a tank with a lot of plants. They will love it for their curious personality. These fishes will explore and hide among the plants in groups.

The plants will not only make them happy but also clean the tank’s water.  They can keep the water quality at optimal conditions, while providing your cuties with places to hide in and feed on.

As mentioned, they eat plants and algae in the wild. It will help to somehow mimic their natural surroundings with a lot of plants to make them feel at home easier and allow them to adapt to the new community.

If you love aquascaping, then it is also your time to show your skills.

These danios love plants, so they can become your instant favorite if you love designing the tank.

These environments are a delight for the danios because they offer them lots of places to explore at the bottom of the tank, their favorite place in captivity.

They’ll surely appreciate your effort of adding a lot of plants in the tank.

Any of the popular tank plants will do well, so you have plenty of choices.

You can also consider driftwood and rocks for the tank because these lovelies also love a lot of hiding places.

They can make them feel stress-free and comfortable if housed in a tank with more of these decorations along with plants.

I would suggest using dark fine sand because it’s easy to clean and it’s good for plants.

But anyway, there are a lot of choices when it comes to substrate to decorate your tank with. 

Anything will work just fine since the galaxy rasbora is not a digger like others. However, it will be better to go for the type of substrate that can work well with the type of plants you decide to add in the tank.

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Another thing to consider for the setup is a filtration system. Like other fish species, they don’t live well in a polluted tank, and this makes them prone to diseases.

To keep them healthy, invest in quality filtration, which can keep the tank clean. You can find a canister filter or hang on the back filter in many online retailers.

But then, the pearl danios are very small, so you should make sure to fill the inlet tubes with a lot of sponges.

They don’t require strong air bladders and air pumps, as they only need a slow flow rate. This can mimic their natural living environment in the wild.

Tank Mates

They can live peacefully with other species in the tank, but you can keep them in a species-only tank to make it simple. This will also help you set up your tank with the right water parameters correctly because they would require a similar one. 

However, do not keep them with aggressive and large fishes to prevent them from sustaining injuries.

You should also ensure that you keep them in a tank with fishes that have the same requirements, ensuring all of them will live comfortably. 

You can consider the emerald dwarf rasbora or Danio erythromicron to house with the margaritatus because they almost have the same maintenance and care requirements.  You can keep them in larger tanks, which can accommodate each of their minimum group size requirements.

Alternatively, freshwater shrimps and snails can also be kept with the same tank as the pearl danios.

If you have a larger tank and you would love some activities in the aquarium, you might also want to add the endler’s livebearers with your danios, which can add life to your tank with their active behavior.

The pygmy hatchetfish is also an excellent choice when thinking about suitable tank mates for the CPDs.

Generally, excellent tank mates to stock your tank with celestial pearl danios include –

  • Cory Catfish
  • Endler’s Livebearer
  • Red Cherry Shrimp
  • Tetras (regular, green, and ember)
  • Killifish
  • Amano Shrimp
  • Honey Gourami
  • Guppies
  • Sparkling Gourami

Food And Diet

When feeding them, you can swish your clean fingers on the top of the tank to ensure that the food you’re giving sinks. It is because they tend to spend much of their lives at the tank’s bottom.

They are not picky eaters in general and require an omnivore diet, making them flexible in terms of food and diet.

In the wild, they normally feed on plants and algae, with planktons being the crowd favorite. For protein source, they also eat small vertebrae.

They can be satisfied with pellets and flakes; however, check that they are high in quality to ensure a balanced diet.

It will also be wise to feed them with sinking pellets, ensuring that they’ll get into the fish.  

Do not give them a lot of food to avoid polluting the tank. You must observe their feeding habits because you don’t want to overfeed them.

Make sure that they can consume everything you give them in minutes. If not, you must reduce it the next time you feed them to avoid polluting the water in the tank.

When choosing their food, take note of their mouth size and body size. It is one of the hardest parts of selecting food for them.

A good choice can be micro pellets and high quality flakes. I’ll also recommend giving them a variety of food. This will not only satisfy them but also make them happy.

I love giving mine with some protein-rich snacks, such as grindal worms, krill, live daphnia, and brine shrimp.  They particularly love brine shrimps that they always find delightful.

Live foods might be hard to get a hold of given the size of the pearl danios. However, they are packed with nutrients that can keep your fish happy and healthy.

You can incorporate them into the diet of your danios or give them as a treat from time to time.  


It is quite easy to breed the celestial pearl danios, so even beginners will not have a hard time on it.

Unlike other fishes that need a certain season to breed, the CPDs don’t have a particular breeding season. In fact, just giving your pearl danios with quality live food can help in encouraging it.

However, do take note that these species are egg layers, with the females looking for laying spots in the tank.

Typically, they search for a place with a low water flow, which is around the plants in many cases.

A female can lay up to 30 eggs at once, and these cute eggs are very small.

A little advice: You should watch out and monitor their location in the tank because males will look for and eat them.  For this reason, remove and put the eggs in a spawning tank once they’re laid.

The eggs in the spawning tank will incubate between two and four days, and then, they will hatch.  To keep them healthy and help them survive, you must feed them with micro food.

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Having a well-planted tank is inviting and accommodating for the fry. They will feed off the plants. As they mature, you can start feeding them with small worms, baby brine shrimp, and fish flakes.

The fry will become adults when they reach three months of age.

Water Quality And Parameters

Like other fish species, they need quality water to prevent diseases and survive.

It will keep them happy and comfortable to live in a clean tank, so you should consider water changes regularly depending on the bioload of your tank.

When it comes to parameters,they prefer an environment that can mimic their natural habitat.  Typically, you will find these fishes in the shallow ponds with lots of vegetation. This can keep the water pure, clear, and clean.  

Vegetation surrounding their natural habitat also ensures that the water maintains low mineral and salt levels. When setting up the tank, keep this in mind. It will help prevent stress and discomfort for the fish. 

Water hardness must be kept between 2 and 10 dKH and pH levels between 6.5 and 7.5.

Meanwhile, water temperature must be kept at optimal levels, ideally between 73 and 79 degrees Fahrenheit.

I’d recommend investing in a quality water test kit to monitor these parameters. It will help you check these things and adjust accordingly.

Distribution And Availability

These species, which are very common in the wild, are found in the basin area of the Salween River (Shan Plateau), Myanmar. 

They are native to freshwater ponds with grasslands and rice paddies surrounding them.

The ponds are shallow with a depth of at least 12 inches (1 foot) and are slow-moving.

As there are a lot of aquatic plants, CPDs can thrive and live harmoniously in this part of the pond, where an ideal spawning ground and shelter is, too.

However, they almost disappear on the face of the planet due to the high demand and popularity among hobbyists.  Thanks to captive breeding that allows these species to flourish and once again increase their population.

You may find CPDs in local pet shops and specialty stores as well as online retailers at varying prices.

Typically, they’re sold in shoals of five to 10 fishes and a cost ranging from $10 for one fish up to $70 for a group of 10 fishes. 

Frequently Asked Questions

Do Celestial Pearl Danios Need Heater?

No, they do not require a heater. You can keep them at room temperature.

They want to be kept in the low to the middle temperature range up to 70 degrees Fahrenheit.

These lovelies can also keep up with lower temperatures like 65 degrees Fahrenheit and higher ones up to 80 degrees Fahrenheit. However, I recommend keeping them at their general temperature range requirements.

How Many Danios Can I Put In A 10-gallon Tank?

The general rule is up to 10 danios in a 10-gallon tank. But then, I suggest keeping your tank a celestial pearl danio only tank. You can keep it under 10 danios in a tank this size, too, or add some cherry shrimps.

Can Danios Live In A Heated Tank?

Yes, they can live in a heated tank. A heater will help, although you can keep the tank temperature between 65 degrees to 75 degrees Fahrenheit even without it. To encourage breeding, a higher temperature like 78 degrees Fahrenheit is advised.

How Many Celestial Pearl Danios Should Be Kept Together?

You should keep six to seven celestial danios in a tank, ideally with the same species only.  Get more females than males, though.

Can Danios Live With Mollies?

You can keep danios with other active fish species like mollies, red eye, serape, platie, skirt tetras, and swordtails. Danios can also be kept with other danios.

However, there are sources claiming that mollies should not be kept with danios, gouramis, angelfish, and other long-finned species because they tend to nip.

Final Thoughts

Celestial pearl danio care is quite straightforward and caring for them suits even beginner hobbyists. 

The galaxy rasbora is an excellent pet fish because they add beauty to the tank. They are also easy to breed, feed, and maintain.

I am a fan of these fishes, and I am highly recommending them to anyone interested to start a fishkeeping hobby. 

I hope that you learn more about these species and ways to care for them in this guide.

You can refer to the above for help on ways to set up the tank, feeding, and breeding your celestial pearl danios.  Keeping this fish is a cinch provided you follow the recommendations outlined here.

Nevertheless, you can start investing on the items you’ll need to set up the tank, but do it little by little. You can research more and take your time until you’re finally decided whether to keep the celestial pearl danios or not.


Passionate fishkeeper. Nature lover. Creative thinker. Music junkie. Adventurer.

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