Jikin Goldfish: Care Guide, Lifespan and More

The Jikin goldfish is one of the rarest Fancy goldfish varieties. Jikins are also known as Sea Wolf, Peacock and Rokurin goldfish. These gorgeous fish have a unique four-lobed tail that’s associated with the Shachihoko dolphin statue in the Nagoya castle. 

Jikins are difficult to come by outside of their native Japan and are almost impossible to rear in the home tank. For that reason, this goldfish is best kept by experienced fish keepers. 

Read this guide to find out everything you need to know about caring for these rare beauties.

Origins Of The Jikin Goldfish

All goldfish varieties originate from a species of common silver-gray carp. In the early 1700s, these Prussian carp were reared in carefully managed ponds for food. 

One day, a fish keeper spotted some brightly colored examples of the carp swimming with the gray ones. The man took the “goldfish” as pets, and the first ornamental pond goldfish was born!

The hobby of breeding goldfish quickly caught on, and soon there were many different color morphs and shapes to be seen. Enterprising breeders saw the opportunity to trade the fish across Asia, and by the 1800s and early 1900s, goldfish had arrived in Europe and the US.

There are now around 200 different goldfish varieties, and the Jikin is one of the rarest examples. 

You won’t see goldfish living in the wild since these fish are exclusively captive-bred. If you spot a goldfish swimming in a lake or river, it will almost certainly be someone’s pet that’s outgrown its tank and been released into the wild. 

Unfortunately, goldfish in the wild don’t generally survive for very long, as their bright colors make them extremely obvious to predators.

What is a Jikin Goldfish?

The Jikin goldfish is a type of Fancy Goldfish that is thought to originate in the Owari region of Japan.

The earliest records suggest that the Jikin was first produced in 1610 by the breeder Suonokami Amano, an Owari clansman. 

The fish was created by hybridizing and mutating a Ryukin-type goldfish that had a long, upright caudal fin. Since that time, the Jikin has been bred in the Nagoya region of Japan, being registered in 1958 as a protected species in the Aichi Prefecture.

These remarkable fish have a distinctive look that distinguishes them from other Fancy Goldfish. Whereas most goldfish come in a variety of colors and patterns, the Jikin is exclusively silvery-white with six red points, specifically on:

  • The dorsal
  • Ventral
  • Caudal
  • Pectoral
  • Anal fins
  • The lips

Breeders artificially adjust these “Rokurin” body colors, typically by removing the fish’s scales with a spatula or the application of plum vinegar.

Jikins have a spectacular split four-lobed tail that’s commonly referred to as a peacock tail and resembles an “X” when viewed from behind.

If you see a pale orange and white Jikin, that’s an older fish. Fading is common and doesn’t indicate health problems.

 Tell us about your Jikins in the comments box below!

Jikin Goldfish Lifespan

Jikin Fancy goldfish are relatively long-lived, often surviving for over 15 years if given the correct care and a high-quality diet. 

What Size Are Jikin Goldfish?

When kept in a domestic aquarium, the Jikin can grow to reach a size of up to 9 inches long

Most Jikins are sold as juvenile specimens of only an inch or so long. Those fish grow quickly in their first couple of years, so we advise you to buy the largest aquarium you can afford so that you don’t need to upscale your setup in the future. 

Price And Availability

Jikin Goldfish are not generally available outside of Japan. If you do manage to get hold of one of these rarities, you can expect to pay upward of £80 ($100).

You definitely won’t find a genuine Jikin for sale in a high street pet store. The only place you’re likely to get one is through an online breeder or auction.

Is The Jikin Goldfish Suitable For Beginners?

Jikin goldfish are peaceful, hardy fish that are pretty easy to care for. On the face of it, that makes these exotic creatures a good choice for beginners. 

However, given that these fish are incredibly difficult to get hold of and are often sold for over £100 per specimen, we advise caution if you don’t have experience in keeping goldfish.

Would you ever get a Jikin Goldfish? Tell us in the comments box below!

Jikin Goldfish Care Guide

In this part of our guide, we explain how to care for the Jikin goldfish.

Jikin Goldfish Tank Size

Jikin goldfish grow to a large size. So, ideally, you want a tank of at least 10 gallons for a single fish, although bigger is better.

If you want to keep more Jikins, you need to allow at least 15 to 20 gallons more for each fish.

Tank Shape

Jikins prefer a long tank that provides them with ample swimming space. All goldfish are oxygen-hungry creatures that need lots of oxygen to keep healthy, and a long tank offers a good surface area for efficient gaseous exchange. 

It’s also a good idea to have a tank with a lid or a cover slide to prevent a startled fish from jumping out. 

A cover can also prevent evaporation and stops dust from settling on the water surface.

Although a goldfish bowl is a traditional container for goldfish, bowls don’t provide anywhere near enough space for these large fish. Also, the small surface area of a bowl is not sufficient for good gaseous exchange.

How Many Jikin Goldfish Can You Keep?

Jikins are gentle, peaceful fish that thrive when kept in groups of similar types. Jikins are average swimmers who can struggle to keep pace with flat-bodied goldfish varieties, especially at feeding times.

If the Jikins are bullied or buffeted around by their companions, stress results, causing a compromised immune system and outbreaks of disease. Slower fish can also be injured by their more boisterous companions.

Therefore, it’s generally recommended that you allow 1 gallon of water for every 1 inch of fish that you wish to keep. That said, the more space you have for your Jikins, the better.

Water Parameters

Temp (oF)pHHardnessAmmoniaNitrate
68o – 78o F6.0 – 8.05 – 19 dGH0>30ppm

Jikin goldfish can live in cool water, preferring the temperature to be within the range of 68o and 78o Fahrenheit. The water pH should be between 6.0 and 8.0, with a water hardness of between 5 and 19 dGH.

The water should contain zero ammonia and nitrites, and nitrate levels must be below 30ppm.


Jikins are like swimming garbage disposal systems, continually excreting whatever they eat and producing a vast amount of waste in the process. 

That means you’ll need a highly efficient filtration system to handle the mess the fish make. 

Your filter system should circulate the total volume of tank water through the filter media at least four times an hour.

Although Jikins are reasonable swimmers, we recommend that you use a filter with an adjustable outflow valve to moderate the flow through the tank. Alternatively, you can buffer the current against plants or decorations.

Tank Maintenance

Weekly water changes of up to 30% are required to keep nitrate levels down and ensure that the environment is safe for your fish.

You’ll also need to use an aquarium vacuum to remove organic waste and plant debris. 

Solid waste tends to gather around plant bases, in the corners of the tank and underneath ornaments and filter boxes, so be sure to pay plenty of attention to those areas.

Goldfish enjoy eating algae and like to graze on patches of the tasty green stuff throughout the day. So, although you don’t want your viewing panes covered in slimy gunge that obscures your view of your Jikins, you might want to leave a small patch of algae for your fish to enjoy somewhere out of sight.

If you have living plants in your aquarium, you’ll need to trim broken stems and remove dead leaves regularly.

Tank Decoration

You can choose whatever decoration scheme you prefer for your Jikin’s tank. However, there are a few things to bear in mind when aquascaping your aquarium. 

Safety First

The Jikin’s gorgeous peacock tail can be vulnerable to damage if it gets snagged on anything sharp or rough. 

Avoid spiky twisted roots, rough resin ornaments, and sharp plastic plants. Instead, choose smooth glass pebbles, flat stones, and driftwood, together with a smooth substrate.

How do you decorate your goldfish tank? Let us know in the comments below.

What About Plants?

The addition of living plants is an excellent idea for your Jikin tank. Plants are not only aesthetically pleasing, but they remove CO2 and nitrates from the water and give off oxygen that helps to oxygenate the water for the fish.

Jikins are not as destructive when it comes to plants as some varieties of goldfish. So, if you choose tough plant species for your aquarium, they should survive. 

Popular plants that are inexpensive, readily available and suitable for your Jikin tank include Anubias, Marimo Moss Balls and Java fern.

If you’d rather not risk using living plants and you don’t want the hassle of maintaining them, you might prefer to use silk ones. Silk plants won’t get eaten by the fish, and you can quickly replant them if they are uprooted.


Living plants need around eight hours of light every day for photosynthesis. 

Aquarium-kept fish need a clear night and daylight cycle to thrive, so they can also benefit from having lighting in the tank. When the lights come on in the morning, the fish know that it’s time to feed and start foraging, and when it goes dark at night, the Jikins understand that it’s rest time. 

If the fish are deprived of that night/daylight cycle, their immune systems can be compromised, leading to outbreaks of disease and failure to thrive.

If you don’t have a lighting unit with an auto-timer feature, you can use a cheap timer plug instead.

Nutrition and Feeding

Like all goldfish, Jikins are omnivores that eat a varied diet of meaty proteins and plant matter, including green algae.

A good daily diet for your fish should include:

  • A portion of high-quality goldfish pellets or flake food
  • Some frozen meaty food, such as bloodworms, daphnia, and tubifex worms
  • Some fresh veggies, including peas and zucchini. 

If you want to, you could leave a small patch of algae for the fish to graze on between feeds.

What About Live Foods?

Although Jikins will eat live foods, we advise against buying live worms and daphnia from your local pet store. Unfortunately, these live foods often contain parasites that you definitely don’t want to introduce into your fish tank.

However, if you’re keen to include live foods in your fish’s diet, you might want to consider setting up a home brine shrimp hatchery.

How Much Should I Feed My Jikin Goldfish

Jikin goldfish should receive two or three small meals daily. 

Offer your fish only what they will clear up in a couple of minutes so that you don’t overfeed them.

What Are Good Tank Mates For Jikin Goldfish?

Jikin goldfish are gentle, peaceable creatures that thrive when kept in company with other goldfish. 

Ideally, you should stick to other Fancy goldfish types as tank mates for your Jikins. 

The best combination to choose is goldfish types that have similar swimming styles so that no one goes hungry at feeding times. 

Other good tank mates for Jikins can be large shrimps and snails, provided that the invertebrates aren’t small enough to be regarded by the goldfish as potential snacks!

Health and Diseases

Despite their delicate appearance, Jikins are quite hardy goldfish. However, there are a few common health problems they can suffer from that you should be aware of.

White Spot Disease

White Spot Disease is also commonly referred to as Ich or Ick.

The condition is actually caused by an aquatic parasite that generally attacks stressed or weakened fish. 

Infected fish usually flash or rub against solid objects in the tank. Eventually, a rash of tiny spots appears on the fish’s skin, fins, and gill covers.

Fortunately, Ich is relatively easy to treat with an over-the-counter medicine that you’ll get in a pet store.

Bacterial Infections

Bacterial infections can affect your fish in different ways and have varied symptoms, depending on the species of the bacterium responsible. The following signs are usually indicative of a bacterial infection of some kind:

  • Ulcers
  • Lethargy
  • Damaged, frayed fins
  • Missing scales
  • Lack of appetite
  • Breathing difficulties

Broad-spectrum antibacterial medication is generally effective against most minor bacterial infections.


External parasites, such as fish lice, anchor worms, and skin flukes, can attack coldwater fish.

Flukes usually get into your fish tank or pond on live food, hidden in plants, or latched onto new fish. 

Keep flukes out of your tank by placing new fish into a quarantine tank for at least two weeks and treating the tank water with an antiparasitic drug.

Breeding Jikin Goldfish

Jikins are extremely difficult to breed, which is why there are so few of them available in the trade.

If you have a tank that contains only Jikins, there’s a slim chance that the fish might breed naturally, provided you have a mixture of males and females. 

The two sexes look very similar, but here’s how you may be able to tell them apart:


Usually develop white pimples called tubercles on their heads when in breeding condition.

Generally bigger and wider than males

Jikins are egg layers. Once the female has deposited her eggs, usually on a flat stone or a dense clump of plants, the male fertilizes them. 

Unfortunately, goldfish will eat their eggs, so we recommend that you use a separate breeding tank so that you can remove the adults once the eggs are fertilized.

However, since the Jikin’s coloration is artificially manipulated as explained earlier in our guide, it’s unlikely that your juvenile fish will develop the characteristic adult markings that are so prized.

Final Thoughts

Jikin goldfish are extremely rare fish that you won’t find for sale in your local pet store. If you do manage to find Jikins for sale online, you can expect to pay top dollar for them.

Although they look delicate and exotic, Jikins are easy to care for and are remarkably hardy creatures. 

Provided that you give the fish a large tank, clean water, and a balanced diet, your Jikins should live for 15 years or more.

Do you keep Jikin goldfish? Where did you find your rare fish? Tell us about your Jikins in the comments box below!

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