TankBud

Variety of Goldfish

Ranchu

Carassius auratus

One of 12 varieties of Carassius auratus · See all varieties →

Also known as Buffalo-head goldfish, Japanese lionhead, King of goldfish

FreshwaterFish

Ranchu (Carassius auratus)
Lawrencekhoo · CC BY-SA 4.0

Varieties · Carassius auratus

See all 12 →

Care at a glance

Temperature
61–75°F
16–24°C
pH
6.5–8.0
Adult size
7.1 in
18 cm
Minimum tank
25 gal
95 L
Temperament
Peaceful
Social behavior
Social
Tankmates
With caution
Swim level
Middle
Difficulty
Medium
Breeding
Medium
Rarity
Common
Family
Cyprinidae
Origin
A dorsal finless fancy goldfish refined in Japan from the Chinese lionhead, bred from domesticated Carassius auratus native to East Asian freshwater.

Overview

House one ranchu in at least 95 L, adding about 40 L per extra fish, with gentle filtration since it dislikes strong flow. Target 16 to 24 C and a pH of 6.5 to 8.0. Keep it only with other slow fancies such as lionheads, orandas and moors. Feed sinking pellets and vegetables, and watch that faster tankmates do not outcompete its slow, near sighted feeding.

In the wild

The ranchu is a dorsal finless fancy goldfish with a strongly arched back, a tucked tail and a wen that covers the head. It swims slowly with a wobbling motion and cannot manage any current. Prized in Japan as a top view fish, it is often kept in shallow tanks viewed from above. Keep it in cool, clean water around 16 to 24 C.

Good to know

The ranchu was refined in Japan from the Chinese lionhead and is nicknamed the king of goldfish for its show status. It has no dorsal fin at all, a trait fixed by selective breeding. The heavy wen is skin tissue that can grow over the eyes and needs clean water to avoid infection.

Did you know

Ranchu are judged from above in Japanese competitions, so breeders select for the curve of the back and tail as seen from the top rather than the side.

Common questions

Is a Ranchu a different species from the Goldfish?

No. A Ranchu is a variety of the Goldfish, Carassius auratus. It is kept the same way apart from difficulty, adult size, tank size and temperature.

What size tank does a Ranchu need?

A Ranchu needs at least 25 gal (95 L). It spends most of its time in the middle.

How big does a Ranchu get?

An adult Ranchu reaches about 7.1 in (18 cm).

Related species