Maximum size : 10 cm

Black Moor Goldfish - Carassius auratus : Complete Fish Profile & Care Guide

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The elegant Black Moor Goldfish (Carassius auratus) is one of the most popular varieties among hobbyists and collectors worldwide. Their unique beauty and hardiness make them an excellent choice for pet owners, especially those who enjoy outdoor ponds. However, despite their resilience to colder temperatures, it is essential to monitor the cooling process to avoid sudden temperature drops that could harm your fish. These fish are perfect for beginner aquarists due to their ease of care.

These Goldfish are incompatible with highly competitive tankmates, as their protruding eyes can cause poor vision and make them less successful at finding food. Therefore, it's recommended to keep them with other similarly handicapped species, such as the Telescope Goldfish, Celestial Goldfish, and Water Bubble-Eye Goldfish. When well-cared for, Black Moor Goldfish can reach up to 25 cm, with a typical lifespan of 10 to 15 years, but sometimes reaching 20 years or more in a suitable environment.

For optimal care of these Goldfish, it is advisable to provide a generously proportioned aquarium, ideally measuring around 1.2 meters in length, allowing ample space for adult fish to thrive comfortably. In this context, the dimensions of the tank, particularly its length and width, take precedence over its height. Given the rapid growth rate exhibited by fancy goldfish, it is prudent to offer them the largest possible aquarium right from the beginning. This practice not only ensures a safer and more stable environment but also facilitates enhanced water quality and temperature stability, thanks to the larger volume of water provided.

The Black Moor Goldfish boasts an egg-shaped body and velvety black metallic scales accentuating its large, bulbous eyes and long, flowing fins. Juveniles have a dull bronze colour with nondescript eyes, but they eventually mature to their signature black hue and telescopic eyes. While most individuals remain black, some may change colour with age or warmer water conditions. They are also available with different tail types, including the veil tail, butterfly tail, broad tail, or ribbon tail. In conclusion, Black Moor Goldfish are a stunning addition to any aquarium or outdoor pond, and their unique characteristics and hardiness make them an excellent choice for both beginner and experienced aquarists alike.

Black Moor Goldfish Photos

Sexual Dimorphism

Distinguishing between male and female Black Moor Goldfish can be a daunting task, particularly when they are young and not in the breeding season. Nevertheless, specific characteristics can help identify their gender. Typically, males are smaller and slimmer than females, and during the breeding season, they display distinguishing features such as white tubercles on their heads and gill covers. In contrast, females carrying eggs will have fatter abdomens. Such physical differences are vital in accurately identifying male and female Black Moor Goldfish.

Quick Facts

Scientific NameCarassius auratus
Year Described1758
Other NamesBlack Demekin, Dragon Eye Goldfish, Black Peony Goldfish
Max Size10 cm
Aquarium LevelAll Levels
DifficultyBeginner - Intermediate
Best kept asTrios
Diet & FeedingOmnivore
ReproductionEgg Depositor
LifespanUp to 10 Years

Water Parameters

Water TypeFreshwater
pH 6.0 - 8.0
GH 5 - 19
Ideal Temperature
65 - 72
18 - 22

Natural Habitat

The fascinating history of the Black Moor Goldfish can be traced back to the Prussian Carp species in Siberia, Central Asia. After centuries of selective breeding, these wild carp were transformed into the captivating domesticated species that we know today. In the wild, these Goldfish thrive in slow-moving and sometimes unclean waters, such as ponds, ditches, lakes, and rivers, where they feed on a variety of plants, insects, small crustaceans, and detritus. Today, Black Moor Goldfish are widely available globally and are just one of over one hundred captivating captive-bred Goldfish varieties that are found in modern-day aquariums.


The breeding of Black Moor Goldfish can be a rewarding experience if provided with the proper conditions. These fish are known to spawn rapidly if given the correct environment and can be bred in groups as small as five individuals, although larger groups are preferred as they are social creatures. In captivity, the breeding season must be mimicked as Goldfish will only spawn naturally in the springtime. To encourage breeding, it is recommended to provide a minimum aquarium size of 75 litres and ensure the fish are healthy and free of diseases. In addition, separating males and females for a few weeks before breeding, along with treating them for parasites, can increase their interest in spawning.

Once the fish are introduced into a breeding tank with oxygenating plants and decorated with solid surfaces for egg adhesion, it is crucial to gradually drop the temperature to 60 degrees Fahrenheit and then slowly warm it at 3 degrees daily until spawning occurs. High-protein foods such as earthworms, brine shrimp, or black worms can also help induce spawning. During spawning, males display non-aggressive chasing behaviours towards females, which can last for several days. After that, the fish will intensify in colour, and spawning can last up to three hours. Females can produce up to 10,000 eggs, which the males will fertilize. 

Sticky threads will attach the eggs to the plants or spawning mops. Parents must be removed from the tank after spawning, as they may consume the eggs. The fertilized eggs will hatch within 4 to 7 days, and the fry can be fed speciality foods until they grow big enough to consume baby brine shrimp or flakes. Initially, the fry will be dark in colour, allowing them to hide from larger fish. However, once they reach around 2.5 cm, they will gain their adult colouration and can be introduced to larger fish.

Diet & feeding

Black Moor Goldfish are known to be omnivores, meaning they require a balanced diet consisting of both plant and animal-based foods to thrive. Therefore, while they may nibble on algae in your tank, it is essential to note that they should not be relied upon as a means of controlling any algae issues. When feeding your Black Moor Goldfish, it is recommended to provide them with high-quality flakes that are specifically formulated for fancy Goldfish. In addition, as these round-bodied fish are prone to swim bladder issues, offering them a well-rounded diet can help prevent any potential digestive problems.

As well as fish flakes, supplementing their diet with frozen and freeze-dried foods such as daphnia, bloodworms, tubifex, and brine shrimp can be beneficial. However, it is essential to presoak any freeze-dried foods in tank water before feeding your Black Moor to aid in digestion and prevent constipation. Feeding your fish once or twice a day is ideal, ensuring that only small amounts of food are given at a time and that everything is consumed within three minutes to avoid overfeeding and potential health issues.

Other Goldfish of interest