Fish
Pearlscale Goldfish
Carassius auratus
Origin: The pearlscale is an ornamental goldfish breed developed by selective breeding in China and Japan. Like all goldfish it descends from the crucian/Prussian carp (Carassius auratus). It does not occur in the wild — it is purely a product of aquarium breeding.
Also known as: Pearlscale, Chinshurin, Carassius auratus
Fact sheet
- Size
- 15 cm
- Lifespan
- 12 years
- Minimum tank size
- 75 L
- Temperature
- 18–23 °C
- pH
- 6.5–8
- Hardness GH
- 8–20 °dH
- Temperament
- Peaceful
- Social behavior
- Schooling
- Group size
- 3+ individuals
- Swimming zone
- Middle, Bottom
- Diet
- Omnivore
- Jumps out
- No
- Eats plants
- Yes
Overview
The pearlscale is one of the most recognisable round-bodied goldfish breeds, named for its domed, pearl-like scales. The body is rounded, almost spherical, with each scale raised into a dome through calcium-carbonate deposits. It is a calm coldwater fish that swims slowly and clumsily because of its body shape. The pearlscale is more delicate than a common goldfish: the round body makes it prone to swim-bladder problems, and the raised scales are easily damaged. Keep it in a roomy tank with soft decor and clean, well-aerated water.
Appearance
The body is short, swollen, and almost spherical, 12–15 cm long. Each scale is domed with a pearly-white centre, creating a distinctive bumpy surface. Colours include orange-red, white, calico, black, and combinations. The fins are paired and the tail is usually forked. High-grade fish may develop a head growth (the 'crown' variety).
Care
A tank of at least 75 L for the first fish plus 40–50 L for each additional one, with soft substrate and no sharp rocks. Temperature 18–23 °C (a coldwater species), pH 6.5–8.0, hardness GH 8–20. Strong filtration, aeration, and regular water changes are essential, as round-bodied breeds are heavy waste producers and sensitive to pollution. Keep decor smooth to protect the scales.
Feeding
An omnivore. Quality sinking goldfish pellets are best: floating food is gulped with air and triggers swim-bladder trouble. Offer blanched vegetables, bloodworm, and daphnia as well. Feed once or twice daily in small portions, avoiding overfeeding.
Compatibility
A peaceful fish kept with other round-bodied goldfish of similar pace — telescopes, orandas, and ryukins. Do not combine with fast long-bodied goldfish or active species, which will outcompete the slow pearlscale. Tropical warm-water fish are unsuitable because of the temperature difference.
Breeding
It breeds like other goldfish: in spring, as temperatures rise, males chase females and eggs are scattered over plants and substrate. Careful selection of breeders is needed to preserve the breed traits. In a community tank the eggs and fry are usually eaten.
Fun facts
The pearl effect comes from calcium-carbonate deposits inside the scales — a damaged scale regrows without the pearly lustre. The variety with a head 'crown' growth is called the crown pearlscale. Its body shape makes it a slow swimmer that needs calm tankmates.