A Complete Guide to Pearlscale Fish Care and Keeping

Pearlscale goldfish (珍珠鱗 chinshurin in Japanese) is one of artificially bread ornamental freshwater fish species (Carassius auratus auratus) that differs from its relatives by the unusual shape of its scales that look like pearls.

Habitat in the wild

Pearlscale is a type of fancy goldfish that belongs to the family Cyprinidae. Fancy goldfish are selectively bred for their unique and ornate features, including a spherical body shape, a high number of dorsal fin rays, and distinctive pearly scales.

The Cyprinidae family, also known as the carp family, is one of the largest families of freshwater fish and includes many well-known species. Some other common fish found in the Cyprinidae family include common carp, koi carp, rosy barb, and cherry barb.

As all species of this kind the fish originates from a common wild carp. The history of pearlscale goldfish can be traced back to ancient China, where selective breeding of goldfish began over a thousand years ago. Goldfish were originally domesticated from wild carp, and through generations of careful breeding, various fancy goldfish varieties, including pearlscale, were developed.

The exact origin of pearlscale goldfish is not well-documented, but it is believed to have been developed in China or Japan during the 19th or early 20th century. Chinese and Japanese fish breeders have long been at the forefront of goldfish development, and they are responsible for creating many of the fancy goldfish varieties we know today.

Over the years, pearlscale goldfish have gained popularity among hobbyists and enthusiasts worldwide due to their unique appearance and gentle demeanor. As with other fancy goldfish, selective breeding continues to refine the pearlscale variety, resulting in a wide range of color patterns and scale configurations.

Today, pearlscale goldfish can be found in many aquariums and ponds across the globe, and they remain a cherished and fascinating addition to the world of ornamental fishkeeping. Their long history and ongoing development serve as a testament to the passion and dedication of fish breeders in preserving and enhancing the beauty of these stunning fish.



The lifespan of pearlscale goldfish can vary depending on the care they receive and their living conditions. On average, pearlscale goldfish can live for around 10 to 15 years in captivity. With proper care, some individuals have been known to live even longer, reaching up to 20 years or more.


Pearlscale goldfish typically grow to be about 5 to 6 inches (12 to 15 centimeters) in length when kept in a well-maintained and adequately sized aquarium or pond. However, some individuals may grow slightly larger or smaller depending on various factors, including genetics, diet, and environmental conditions.


The pearlscale goldfish has oviform short rounded body and it is fat like the one of a fantail fish. All the fins are short. The fish has separate large gibbose scales that look like cut in halves pearls stuck to its body.

If the pearlscale looses this pearl-like scale for some reason, a new one grows eventually, but it has an ordinary shape and doesn’t look like the lost one at all.


Body is often orange, red and white colored, but the most famous and popular coloring is the orange-red one. It is possible to encounter the fish with blurred spots on its body in case of yellow coloring with some other dark color combination. Recently we’ve seen black and calico colored species.

Body ShapeSpherical or egg-shaped body
Scale TypePom-pom or pearl-like raised scales
ColorationVarious colors and patterns, including metallic shades
SizeTypically grows to about 5-6 inches (12-15 cm) in length
Dorsal FinProminent and long dorsal fin
Tail FinDouble-tail or fan-shaped tail fin
Anal FinSingle anal fin
Pectoral and Pelvic FinsPaired fins on the sides and bottom of the body
EyesProtruding and large eyes
BehaviorGenerally peaceful and sociable
LifespanCan live up to 10-20 years with proper care
DietOmnivorous; prefers a balanced diet with pellets and veggies
Tank RequirementsNeed a well-maintained tank with proper filtration
Water ParametersTemperature: 65-75°F (18-24°C); pH: 6.5-8.0
Tank SizeMinimum 20 gallons for one adult pearlscale
BreedingEgg layers, require a separate breeding tank and special conditions
Special ConsiderationsSensitive to poor water quality and overcrowding

Difficulties in keeping

Are pearlscale goldfish hardy? All goldfish species are rather not demanding, since they are ancestors of a common carp which dwells in cold water and isn’t demanding either.

Quite often pearlscale is kept in open waters and the water temperature there is lower than it is required for tropical fishes. Pearlscale is unpretentious as for the food as well.

Care and keeping in a tank

Tank size

The tank size for pearlscale goldfish depends on the number of fish you plan to keep and their expected growth size. Pearlscale goldfish, like other fancy goldfish varieties, require more space compared to common goldfish due to their rounded body shape and potential for shorter swimming abilities.

As a general rule of thumb, it is recommended to have at least 20 gallons (75 liters) of water per adult pearlscale goldfish. However, keep in mind that larger tanks are always better, as they provide more swimming space and help maintain better water quality.

For a single adult pearlscale goldfish, a tank size of 20 to 30 gallons (75 to 113 liters) is a good starting point. If you plan to keep multiple pearlscale goldfish, you will need to increase the tank size accordingly to accommodate their needs.

As these goldfish can grow to around 5-6 inches (12-15 cm) in length, providing a spacious environment is crucial for their well-being. Overcrowding can lead to stress, poor water quality, and health problems, so it’s essential to plan ahead and invest in an adequately sized tank for your pearlscale goldfish.


These fish love digging the tank bottom substrate, that’s why it’s better to use pebbles or large grained sand for this purpose. This way the fish won’t scatter the substrate that much. Some goldfish keepers prefer to have a bare-bottom tank for easier maintenance and cleaning. Bare-bottom tanks also prevent any substrate from being ingested by the fish, reducing the risk of digestive issues.

When choosing a substrate, keep in mind that pearlscale goldfish tend to be bottom feeders, and they may accidentally ingest small particles while foraging for food. It’s essential to avoid any sharp or small substrates that could potentially cause harm or be ingested.

Tank decor

Though the plants may be both artificial and live ones. The latter should have strong roots and coarse leaves. Plants like anubias will do perfectly well for this tank. The fish won’t eat them and they will help to create proper ecological environment in the tank.

However, pearlscale quickly damages tank plants with soft leaves or the leaves surfaces gets dirty because the rubbish (produced by the fish) lays on them. None of tank decorations whether these are stones or snags should have sharp edges that may hurt the body or fins. Leaving some free space in a tank for a pearlscale to swim is a must.

Tank lighting is not necessary, but nevertheless the fish shows all its beauty when the lighting is on.

Water parameters

The tank water parameters should be the following:

  1. Temperature: 65°F to 75°F (18°C to 24°C). The ideal temperature range for pearlscale goldfish falls within this range, and it is essential to avoid rapid fluctuations in temperature.
  2. pH Level: 6.5 to 8.0. Pearlscale goldfish can tolerate a slightly wide pH range, but it’s essential to keep the pH stable to prevent stress and health issues.
  3. Ammonia and Nitrite: 0 ppm. Both ammonia and nitrite are highly toxic to fish, so it’s crucial to maintain a tank with zero detectable levels of these substances. Regular water changes and proper filtration help control ammonia and nitrite levels.
  4. Nitrate: Below 40 ppm. Nitrates are less harmful than ammonia and nitrite but can still be detrimental to fish health at high levels. Regular partial water changes help keep nitrate levels in check.
  5. Hardness: 5 to 20 dGH (degrees of General Hardness). Pearlscale goldfish can tolerate a moderate range of water hardness, but it’s best to avoid extremes.

It’s essential to monitor water parameters regularly using a reliable test kit and make adjustments as needed to maintain a stable and healthy environment for your pearlscale goldfish. Additionally, regular partial water changes (about 20-30% every 1-2 weeks) can help keep water quality optimal.


Keep in mind that goldfish produce more waste than many other fish species, so a larger tank with efficient filtration is crucial to maintaining good water quality and preventing overcrowding.


The diet of pearlscale goldfish should be well-balanced to meet their nutritional needs and promote good health. As omnivores, pearlscale goldfish require a mix of both animal and plant-based foods. Diet should contain 50-70% of vegetable components and 30-50% of protein food.

Here are some dietary guidelines for feeding pearlscale goldfish:

  1. High-Quality Pellets or Flakes: Choose high-quality commercial pellets or flakes specifically formulated for goldfish. Look for products that offer a good balance of protein, carbohydrates, vitamins, and minerals.
  2. Fresh or Frozen Foods: The pearlscale usually eats live and frozen food: brine shrimp, daphnia, tubifex; also it likes dry food very much. These foods provide essential protein and nutrients.
  3. Vegetables: Provide some vegetable matter in their diet. Blanched or steamed vegetables like peas, zucchini, spinach, or lettuce are excellent choices. Vegetables aid digestion and add variety to their diet.
  4. Avoid Overfeeding: Overfeeding is a common issue with goldfish and can lead to health problems and water quality issues. The main thing is not to overfeed it, since this leads to bowel obstruction. It is especially dangerous to overfeed with a bloodworm, because it causes flatulence and the fish looses its balance and dies as a result. You should feed twice a day – in the morning and in the evening.
  5. Avoid Feeding Processed Human Foods: Avoid feeding them processed human foods, as they may contain ingredients harmful to goldfish.

Always remember to monitor your pearlscale goldfish’s condition and adjust their diet as needed. Proper nutrition plays a crucial role in their growth, coloration, and overall well-being. Along with a balanced diet, maintaining good water quality and providing a suitable environment will help keep your pearlscale goldfish healthy and happy.

Tank mates

Is not aggressive or troublesome. However, the fact that the pearlscale goldfish is slow, has long fins and tends to live in cool water puts some limitations when choosing tank mates for it (fishes like tiger barbs – bad choice). Surely, the fish can live in a tropical fish tank, but still it feels better and more comfortable with the species of its kind – goldfish, oranda, veiltail. These fish have similar care requirements and are generally peaceful.

If you have a large enough aquarium, common goldfish can be kept with pearlscale goldfish. However, keep in mind that common goldfish grow much larger and faster than fancy goldfish, so a spacious tank is essential to accommodate their size differences.

Gender differences: male vs female

Male and female are almost indistinguishable from each other. Determining the sex of adult pearlscale goldfish can be challenging, especially when they are not in breeding condition. However, there are some general differences that can help differentiate between males and females:

  1. Body Shape: In some cases, males tend to have a slightly slimmer and more streamlined body compared to females, especially during the breeding season when females may appear rounder due to the presence of eggs.
  2. Pectoral Fins: The pectoral fins, located on the sides of the fish near the gills, are usually longer and more pointed in males compared to females. Female pectoral fins may appear shorter and rounder.
  3. Vent Shape: The vent, located just in front of the anal fin, may be slightly different in males and females. In males, the vent may appear more pointed, while in females, it may be more round or slightly protruding.
  4. Breeding Tubercles: During the breeding season, males may develop tiny white or white-tipped bumps called breeding tubercles on their gill covers, pectoral fins, and sometimes head. Females typically lack these tubercles.
  5. Behavior: During the breeding season, males may become more territorial and exhibit courtship behaviors, such as chasing females and nudging them. Females may show signs of gravidity (carrying eggs) and may become more reclusive.

It’s important to note that these differences can be subtle, and in some cases, individual variations may make it challenging to determine the sex definitively. Additionally, the presence of breeding tubercles and some other sex-related features may not be prominent in all males, especially in young or immature fish.

If you’re interested in breeding your pearlscale goldfish, observing their behavior during the breeding season is one of the best ways to identify potential males and females. Otherwise, unless you have specific breeding intentions, knowing the sex of your pearlscale goldfish may not be crucial for their care and well-being.


The fish is bred in farms. However, you can also obtain the juveniles in a home aquarium. Put some sandy substrate and small leaved plants into a spawning tank. As a rule, for spawning they put one female and 2-3 males (2 years old) in the tank.

The fish should live separately for 2-3 weeks before this. It is recommended to keep water temperature in the spawning tank about 24 – 26 °C. To trigger the spawning process you should gradually rise the water temperature until it becomes 5-10 °C higher

At that the males start actively haunting the female that is dropping eggs all over the tank at the same time. Mainly the eggs stay on the leaves of the tank plants.

In general the female lays about 1000 eggs. Once the spawning is over, remove the ‘parents’ from the tank. Small zooplankton should be the start food for juveniles.