Kokuryu (Black Dragon-eye Pearlscale)

Kokuryu (Black Dragon-eye Pearlscale) key facts

Care level

Advanced

Lifespan

10-15 years

Temperature

20〜23℃

Diet

Omnivore (goldfish pellets as the staple; also bloodworms and daphnia)

Identification

Look for all three: black body, domed pearl scales and protruding eyes. Without protruding eyes it is a Pearlscale; with flat scales, a Black Moor.

Flow & Layout

Pearl scales do not regrow and protruding eyes are easily injured; avoid sharp or hard decor and keep the current gentle.

Water Temperature & Quality

The ideal range for fancy goldfish is about 20-23°C, pH around 7.0-8.4. Avoid sudden changes in temperature or water chemistry.

Container & Tank

Allow roughly 38 L (10 gallons) or more per adult fish, with a generously sized filter.

Diet & Feeding

The spherical body is said to be prone to constipation; give sinking food in small amounts and avoid overfeeding.

Tankmates

Slow and poor-sighted; keep only with other gentle telescope-eyed or round-bodied goldfish.

Notes

Black may fade with growth and some fish turn red, so do not assume the current color is permanent.

About Kokuryu (Black Dragon-eye Pearlscale)

Kokuryu is a black, telescope-eyed pearlscale goldfish. Its black can fade as it grows, and it suits experienced keepers. Learn what to know before you bring one home.

7 things to know before welcoming a Kokuryu (Black Dragon-eye Pearlscale)

1. 1For experienced keepers

   Kokuryu is rated as a variety for experienced keepers. There is a lot to watch, including the delicate eyes, the rounded body, and possible color changes, so it is best to gain goldfish experience first. If anything worries you, ask the seller before you commit.

2. 2Protect the eyes

   The protruding eyes are easily bumped or scraped by hard decorations, sharp edges, or strong currents. Avoid anything rough or pointed and use only smooth items in the tank. An eye injury can lead to further problems, so check the eyes every day.

3. 3Black may fade

   The black can fade as the fish grows, so the color you see at purchase may not last into adulthood. The depth of black varies between individuals, so check photos carefully and be ready to enjoy any changes. Asking the seller about the parent fish or how similar fish developed can be helpful.

4. 4Round body, balance

   Pearlscales have round bodies and are not strong swimmers. Keep the current gentle and set up a tank where the fish can move without effort. Some individuals lose their balance, so watch daily for any swimming that looks different from usual.

5. 5Feeding carefully

   Telescope-eyed goldfish are said to have limited vision and may take time to find food. They can lose out to faster tank mates, so feed slowly and make sure each fish is actually eating. Remove leftovers promptly, since uneaten food fouls the water.

6. 6Water quality upkeep

   Goldfish produce a lot of waste and foul the water quickly. Set up good filtration and keep the water clean with regular water changes. Sudden shifts in temperature or water quality stress the fish, so keep changes gradual, including during water changes.

7. 7Tank mates and setup

   If you keep it with others, choose goldfish that swim slowly like it does. Fast swimmers may injure its eyes and body or take its food, so avoid them. Set up the tank before the fish arrives, acclimate it carefully, and give it time to settle in quietly.

Frequently asked questions about Kokuryu (Black Dragon-eye Pearlscale)

Q.Can a beginner keep Kokuryu?

A.It is rated as a variety for experienced keepers. The eyes are easily injured and there is more to watch, such as the round body and color changes, so it is safer to gain goldfish experience first.

Q.Will the black color last as it grows?

A.The black can fade as the fish grows, so it may not stay the same shade into adulthood. Individuals differ, so expect that it might change, and ask the seller how similar fish have developed if you are concerned.

Q.How long does Kokuryu live?

A.The lifespan is roughly 10 to 15 years. Plan for a long commitment and set up a suitable environment, including the tank and filtration.

Q.How large does it grow?

A.There is little data on the adult size of Kokuryu, and individuals vary. Plan ahead and give it plenty of room as it grows.

Q.How does it differ from the Ping Pong Pearl?

A.Kokuryu is the black form of the telescope-eyed Ping Pong Pearl. They share the raised pearl-like scales and protruding eyes, and the main difference is the black body color.

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