Shusui Koi

1 Species Overview

The Shusui koi is an asagi-type koi of the German carp line, which is why many cannot tell it from the asagi. By color layout it splits into three kinds: flower Shusui, yellow Shusui, and red Shusui.

Chinese name: Shusui koi

Distribution: China, Japan, Germany

Reproduction: Egg-laying

Climate: Temperate, cold zones

2 Appearance and Physical Traits

The Shusui koi is the asagi-type koi of the German carp line. By color layout it splits into flower Shusui, red Shusui, and yellow Shusui; the scale layout differs by type. What are its traits?

The asagi-type koi of the German line is called Shusui. The Shusui head is clear light blue, the back blue-green, with red on the snout, cheeks, belly, and fin bases—no dark shadow or sesame black dots. German-line koi must have neat scale rows; the Shusui’s top row of deep-blue scales must be strictly neat. Between the top row and the side belly row, lone large scales often appear, called extra scales; best to avoid them. Many large irregular scales are called iron-armor scales and are not worth viewing.

3 Habitat and Living Environment

Like other koi, the Shusui is cold-blooded but cannot take sudden temperature changes; pH 7 to 7.4 is suggested. Keep water stable and it grows healthy.

Choose a tank size by home space, but because the Shusui differs from goldfish in habits—larger body and more active—the tank should not be too small; capacity is best at least 60 kg. For larger Shusui, enlarge the tank to at least 200 kg capacity. Because the Shusui is active and uses much oxygen, fit a filter and air pump for enough oxygen and clean water.

Large tanks or those with many koi can use an air compressor or high-power high-output pump; small or lightly stocked tanks can use a dedicated electric micro air pump. Also the tank needs enough lighting, since the point of keeping Shusui is viewing, so some lighting is required.

4 Feeding Guidelines

Like other koi, the Shusui is an omnivorous ornamental fish that takes both prepared and live foods. How to feed it scientifically for health?

The Shusui is omnivorous; both animal and plant foods work, such as daphnia, tubifex, rice, and dough, but special synthetic koi food is best. In the tank, do not overfeed—seven to eight tenths full by usual viewing is enough, or it causes trouble: mild indigestion, or worse, leftover food spoiling water. Avoid evening feeding.

Feed on a strict schedule and amount to keep water clear. Generally once or twice daily, morning and evening; the evening meal should be early, around dusk. In rain or cooling at dusk, feed little or none; morning feeding can be at dawn. After each meal, judge by whether the fish finish within an hour and by feces color whether digestion is good, to set the next amount.