Often described as a great fish for small garden ponds, shubunkin goldfish are a hardy and gorgeous option for aquarists.
They also happen to be among the largest goldfish varieties, but these gentle giants tend to keep to themselves, and will only get into harmless antics when they’re feeling particularly frisky.
But what else should you know about shubunkin goldfish before bringing them home? Quite a lot, actually—so, let’s dive right into the care and maintenance of these big and beautiful fish, and discuss the specifics that every fish keeper should know!
Shubunkin Goldfish: Origin And Appearance
In general, shubunkin goldfish are a large calico-patterned species, favored by fish keepers for their beautiful looks and gentle nature. And when you see their graceful movements in the water, with their long fins and glittering scales, you can understand why.
Where Do Shubunkin Goldfish Come From?
A Japanese goldfish in origin, shubunkins come from breeding the larger Comet and Calico goldfish types with a common goldfish in the early 1900s. Since then, these big, beautiful fish have been a favorite among large aquarium keepers, as well as those who have small outdoor ponds.
What Do Shubunkin Goldfish Look Like?
Big, vibrant, and mischievous, these are splashy fish to keep in your setup. Shubunkin goldfish have what are known as “nacreous scales”, which refers to their scales being quite opalescent in appearance, as opposed to being metallic or fully transparent.
These scales will be found in calico patterns of blue, black, grey, red, and white, in patches or even speckles that stretch down their backs and sides. Typically, the fins are long, tapered, and mostly transparent, though some coloration can spread past the base of the fins.
When it comes to body shape, shubunkins share a similar appearance with other goldfish types—namely a long, somewhat torpedo-shaped body with big eyes and sloping noses that most aquarists make them absolutely adorable.
How Big Do Shubunkin Goldfish Get?
Among other types of goldfish and even varieties of outdoor pondfish, shubunkin goldfish are some of the largest you can find. They can easily grow to encompass lengths of between 9 and 18 inches when fully matured, although it does take them a while to reach these adult sizes.
Your shubunkin goldfish will grow rapidly over the first year to year and a half of their life, fully maturing at about two years of age, when they reach their full size, depending on the enclosure conditions and individual health.
What Types Of Shubunkin Goldfish Are There?
While referring to them generally as shubunkins is completely acceptable, several shubunkin variants have been bred over the years from the species’ initial emergence into the aquatic life scene.
- American Shubunkins—Often considered to be the original variant, these are also known as “Japanese” shubunkins, and have a long, pointed tail with a deep fork in the middle.
- Bristol Shubunkins—Boasting a more slender body, the Bristol shubunkin tends to be an all-over blue color, with longer tail fins that have a more accentuated point.
- London Shubunkins—Still keeping a calico pattern, London shubunkins will come in a variety of color palettes typical to other goldfish, but it has a slender body and much more rounded fins than their relatives.
Shubunkin Goldfish: Lifespan
Bringing a shubunkin goldfish home is not a choice to be taken lightly, mainly due to their long lifespans. These fish will easily live between 15 and 20 years in the right conditions and when fed a proper diet, meaning that your commitment to this particular type of goldfish will last a couple of decades.
Shubunkin goldfish are hardy and adaptable, which leads to them having such a long lifespan. If kept in an aquarium, they are likely to live closer to the 15-year mark, or even just 10 if their health is not optimal.
However, when kept outside in expansive enclosures, shubunkins will often last for 20 years, and have even been known to live for 30 years.
Shubunkin Goldfish: Behavior
Overall, these goldfish are active, mischievous, and playful, with aquarists noting that they act quite like big, water puppies rather than exhibiting typical fish behavior.
Shubunkin goldfish are highly social and thrive when placed with a companion or two of the same species. They do enjoy getting into a variety of antics, including playing with and chasing each other, uprooting plant life, and general athleticism and frolicking.
Though large in size, these fish are very friendly with humans and other aquatic life alike. They are amiable tank or pond mates for a variety of fish species, as their tranquil and playful nature does not lend them to aggression or bullying.
In fact, shubunkin goldfish have been known to be on the receiving end of nipping or more boisterous fish behavior when paired with unfriendly species, as they do not put up a fight and would prefer to be friends instead.
Shubunkin Goldfish: Compatibility
You should always keep your shubunkin goldfish with at least two other shubunkin companions, as this social fish can get depressed and despondent if they do not have friends to interact with.
But apart from that, what are shubunkin goldfish like when paired with other species? Let’s take a closer look at their communal living capabilities.
Are Shubunkin Goldfish Fish A Communal Tank Fish?
As a highly social species, shubunkin goldfish are great to have in a communal tank. These large fish thrive when placed with companions, and even their size does not tend to get in the way of pleasant interspecies interactions.
However, you do need to be careful of the fish that are placed with shubunkin goldfish, as even their size will not protect these gentle giants from aggressive species like cichlids or tiger barbs. Stick to fish within the same family for the best fit, as well as other passive fish types.
Best Tank Mates For Shubunkin Goldfish
Are you looking to add more inhabitants to your shubunkins’ enclosure or tank? The following species are great tank mates for creating a communal space that shubunkin goldfish will continue to thrive in.
- Koi—A great option, sharing the same original Carp family roots, Koi fish are an ideal tank mate for shubunkin goldfish.
- Large Invertebrates—Including amano shrimp and mystery snails, just make sure these creatures are big enough not to be mistaken for food.
- Other Goldfish—Avoid fancy goldfish that can be easily injured, but don’t be afraid to add other types, including Comet or Calico goldfish, to the enclosure.
- Passive Fish Types—Cherry barbs, glass catfish, guppies, killifish, and tetras are all great options for adding to your setup, as they are peaceful and fast enough to get access to food amid the larger appetites of shubunkins.
Shubunkin Goldfish Care: Habitat And Tank Requirements
Shubunkin Goldfish Tank Size
Because of their size, shubunkin goldfish require a larger enclosure or aquarium setup than other goldfish types. To keep shubunkins in a tank, you need to house them in a 75-gallon tank as the minimum size.
But due to their fast growth and how long they can actually become, it’s better to have a larger tank. Estimate about one or two shubunkin goldfish for every 75 gallons of space in your enclosure, including for indoor tanks and outdoor ponds.
For outdoor enclosures, make sure the pond is at least 28 inches deep, with shallow spots of about 6 inches for feeding. These fish require plenty of room for activities, schooling, and general movement, as they are a particularly athletic species.
Shubunkin Goldfish Water Requirements
These big goldfish are a cold-hardy species, and able to live outdoors, but cannot survive if conditions become freezing. That being said, the most comfortable, active water parameters for your shubunkin goldfish fall between 65°F and 72°F.
If your pond drops below the lower end of this scale but remains open, shubunkin goldfish will sink to the bottom and hibernate until temperatures rise again. However, if it gets cold enough for the water to freeze over, this is dangerous for the fish’s oxygen and nutrient levels, and as such they should not be left out in such conditions.
In terms of acidity and water hardness, shubunkin goldfish thrive when living within pH values of 6 to 8, and with a dGH level anywhere between 5 to 19. These aspects are not as critical as the temperature though.
Shubunkin Goldfish Tank Setup
Give your shubunkin goldfish plenty of room to swim, play, and forage for food, and they will be very happy.
The setup of your tank or pond should also include a variety of plants for them to explore and root around in, but be aware that shubunkins tend to uproot delicate plants very easily in their search for food or during their daily activities. So planting artificial foliage might be best for a shubunkin enclosure.
Medium-sized gravel substrate types are ideal for shubunkin goldfish as well, giving them the option of sifting through it for traces of food or minerals left behind, and will not harm their bodies.
Shubunkin Goldfish Care: Diet
Your shubunkin goldfish is best fed an omnivorous diet that will offer a variety of nutrients and food types, including good quality fish feed and fresh, live treats to supplement it further.
Because shubunkin goldfish is a relative of the carp family, they also require a steady amount of protein in their diet, on top of fish food and vegetables. This can be achieved by giving them frozen or fresh bloodworms, brine shrimp, or even krill meals.
Such high-protein substances should make up about 30% to 50% of their total diet in order to keep your shubunkins healthy and enhance both the span and quality of their lives.
And if you have young fish, this protein ratio will need to be even higher, with diets composed of at least 50% protein necessary for adequate growth and to prevent diseases. As soon as your shubunkin goldfish have matured into adults, you can decrease the protein intake to the lower end of the scale, around 30%.
Apart from protein concerns, using a quality goldfish pellet or flake food mix is great for base nutrition. But the remaining 70% or so of your shubunkins’ diet should be made up of vegetables and plants, including the following foods:
- Cucumber.
- Lettuce.
- Oranges.
- Shelled & Cooked Peas, Cooled.
- Spinach.
- Spirulina.
- Tomatoes.
- Watermelon.
- Water Hyacinth.
Feed your shubunkin goldfish fish pellets or flakes several times a day, alongside a variety of proteins, vegetables once a day, and fruit once every few days.
Mastering the diet is one of the things that makes keeping shubunkins challenging at times, but once you establish a routine feeding schedule it will become second nature!
Shubunkin Goldfish Care: Breeding
Your shubunkins will spawn under the right conditions and without much intervention from their keepers, so breeding them is surprisingly achievable for most people.
The overall process of breeding your shubunkin goldfish starts by separating a spawning group of about four or five individuals into a breeding tank, away from other fish and fellow shubunkins.
This tank should also have plenty of plant life to catch and harbor the fish eggs, and can be real or artificial.
By dropping the water temperature in the breeding tank gradually to around 60°F, and then slowly raising it by one or two degrees every day until the water reaches 72°F, this should stimulate the fishes’ breeding instincts and prompt spawning to begin in the warmer conditions.
Once the eggs have been laid amid the tank’s plant life, it’s important to remove the adult shubunkins from the tank, as they will eat both eggs and very young spawn.
The eggs will hatch in about a week and the fry will continue to grow quite quickly, able to be reintroduced to the adults when they are at least one inch in length.
Shubunkin Goldfish Care: Health And Wellness
Changing the water in your shubunkin goldfish enclosure is essential to keeping the inhabitants healthy and free of diseases. To prevent common parasites or bacteria from appearing at harmful levels, carry out a 25% aquarium water change every one to two weeks without fail.
Outside of keeping their environment clean and bacteria-free, keep an eye out for a few routine diseases that can affect your shubunkin goldfish.
This includes Goldfish Ich, a very common illness among goldfish in aquariums which manifests as white spots all over your fishes’ bodies, leading to “scratching” behaviors that can damage their scales.
Swim bladder disease and fin rot are other illnesses that can affect your shubunkin goldfish, and should be treated immediately if you notice your fish becoming lethargic or having difficulties swimming.
FAQ
Shubunkin goldfish is one of the most beloved types for inhabiting a large aquarium setting or outdoor pond, and are fairly straightforward fish.
However, the following information about shubunkin goldfish is great to school yourself on, should you have any questions of your own that remain!
How Big Does A Shubunkin Goldfish Get?
Being among the largest types of goldfish, shubunkins typically grow to reach adult sizes between 12 and 18 inches in total length, over the course of one and a half to two years as they mature into adult fish.
In fact, juvenile shubunkin goldfish can grow up to one entire foot in a single year, making them some of the most impressive growers in the aquatic world.
How Do You Take Care Of A Shubunkin Goldfish?
These large, amiable goldfish do have specific dietary and enclosure needs, but apart from these conditions, shubunkin goldfish are fairly easy to care for. They require companionship, a proper diet, and an adequate tank or pond set up to keep them busy and active.
If you have the space and time to dedicate to these types of fish, they are a great addition to an aquatic setting and are actually ranked as low to medium on most pet care difficulty scales!
Do Shubunkin Goldfish Need A Heater?
Because shubunkin goldfish are adaptable in terms of water temperature and hardy enough to withstand living in an outdoor pond, a heater is not always necessary to keep them healthy.
If you live in a very cold environment that risks freezing over an outdoor fish pond completely, then you should bring your fishy friends indoors over the winter anyway to avoid lowered oxygen levels and impeded access to nutrients, which even a heater will not help.
How Often Should You Feed Shubunkin?
Because of their layered dietary needs, you should be feeding your shubunkin goldfish on a staggered schedule, depending on the type of food.
Fish flakes or pellets and protein sources should be fed several times a day, vegetables once per day, and fruits dispensed every three days or so.
Always make sure to clean out any food remnants that are not eaten by your fish to avoid putrefaction and the dangers of nitrogen levels rising and causing excessive algae growth.
Can Shubunkins Change Colour?
Shubunkin goldfish have been known to have slight changes to their coloration or even patterns as they mature, as other goldfish types can also experience.
However, shubunkins tend to be more established when it comes to color, usually only losing black speckles on their bodies as they age instead of changing hues entirely.
Final Thoughts
When you think of goldfish, you might be thinking of the small ones that swim in a round fishbowl.
However, shubunkin goldfish are more along the lines of Koi in both size and ability to exist in an outdoor pond, making them both a great option for those who have the room, and a definite commitment.
But these gentle giants are really some of the best additions to your aquarium setup, and with their wonderful personalities and impressive athletic abilities, you will be guaranteed hours of enjoyment when you have shubunkin goldfish!

Hi, my name is Adam and I’m an aquarium enthusiast! I didn’t discover the joys of being an ‘aquarium fanatic’ (as some of my friends call me!) until I was in my 20’s. When I first started out I found it difficult to find all the information I needed so I started this website to compile all the useful information I can think of. Enjoy!
Table of Contents