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The Izumo Nankin Goldfish is a rare breed of goldfish outside Japan, although it is easier to find and popular in the Southwest of Japan, where it originates. There are Izumo Nankin Goldfish clubs and breeder groups in Japan, but in other countries, you will find it very difficult to source one of these fish. Known for their bright color, the fish is especially notable for its top-down view, thanks to its triangular shape.
It is considered a peaceful species, like most goldfish, but you do have to take care when housing them with larger species that might try and eat them because of their placid nature.
Quick Facts about Izumo Nankin Goldfish
| Species Name: | Izumo Nankin Goldfish |
| Family: | Goldfish |
| Care Level: | Moderate |
| Temperature: | 45°F–53°F |
| Temperament: | Placid |
| Color Form: | White and red/gold |
| Lifespan: | 10–15 years |
| Size: | 8–9 inches |
| Diet: | Plants and pellet/flakes |
| Minimum Tank Size: | 10 gallons per fish |
| Tank Set-Up: | Large with a good filter |
| Compatibility: | Can live with other placid fish |
Izumo Nankin Goldfish Overview
First bred around 1750 in the Shizuoka Prefecture of Japan, now known as the Shizuko Prefecture. The fish had existed prior to this date, but it was improved upon and perfected around 1750 according to the wishes of clansman Fumai Matsudaira. The fish continued to be bred in the region and was rarely sold or bred outside the area. In 1982 it was registered as a protected species and it remains very difficult to source outside Japan. It may be possible to contact a breeder in Japan and have one shipped to your current destination but this can prove costly and the journey can be difficult.
They can be difficult to breed, and although they don’t have any unusual or specific care requirements, they do tend to dig up their gravel substrate which means that you will need to clean the tank out frequently. For these reasons, they are not considered the best choice of breed for beginners. Although they can be kept with other placid fish species, they shouldn’t be kept with fish that might try to eat or attack them because they are so placid they won’t defend themselves.
How Much Do Izumo Nankin Goldfish Cost?
When available, Izumo Nankin Goldfish are relatively inexpensive. They can be purchased for as little as $10, however, they are typically only available in Japan which means that you will have to pay transport costs. If you are in Japan yourself and can safely transport the fish back, this is one option. Alternatively, however, you will have to pay to have the fish transported over. Paying for the safe shipping of goldfish is prohibitively expensive and will cost much more than the price of the fish and likely even more than the price of your tank and setup.
You may be able to find somebody that has Izumo Nankin fish of their own, and has bred them, but this will take a lot of search and research and the cost will likely be higher.
Typical Behavior & Temperament
The Izumo Nankin is a placid fish that won’t attack others. It isn’t territorial so it won’t attack other Nankins and it won’t try to eat or attack smaller fish in the tank. Therefore, it makes a good addition to a multi-species school. They do have a tendency to eat plants and may even try to eat artificial plants, so the species does better in a tank with minimal artificial plants and only real plants that are safe for the species.
The Nankin is also known to dig up the gravel substrate, and this can cause dust and dirt clouds that you will need to clean up to ensure a healthy living environment for your goldfish.
Appearance & Varieties
The Izumo Nankin is a gold and white fish. An ideal coloration is a good combination of the two colors. Some Nankins can be completely white while others can be completely orange. Because of the desire for the fish to combine gold and white, some owners apply plum vinegar to the orange areas of the fish. The vinegar safely removes the color pigment in the areas applied, leaving the white color behind.
The Nankin grows to approximately 3 or 4 inches but may grow a little larger. They have long fins that extend from the body, which is triangular in shape. The species has a small head and no dorsal fin. The tail is a twin-tail and the fish has small eyes.
There are no known variants of the Izumo Nankin, although they can come in a variety of colors and patterns.
How to Take Care of Izumo Nankin Goldfish
The Izumo Nankin is typical of most goldfish in regards to its requirements. It can be fed flake or pellet food and requires a suitable temperature and pH level to thrive.
Habitat, Tank Conditions & Setup
The Izumo Nankin is a relatively undemanding fish that generally requires a large but reasonably bare tank. You do need to maintain a suitable temperature and pH value but, other than this, the biggest concerns will be preventing the fish from eating substrate and cleaning the tank of dirt and debris kicked up from the gravel substrate.
Tank Size
The absolute minimum tank requirement for this species is 10 gallons per fish, but an ideal size would be 20 gallons for each Nankin you house.
Water Quality & Conditions
The Nankin needs water temperature between 43°F and 53°F as well as a pH value between 6.5 and 7. Specific gravity should be 1.008 or 1.009 to maintain soft gills without causing stress. You will need to clean the water regularly as this species is known to dig up its gravel, causing dust clouds.
Substrate
Pebbles or river rocks are the preferred substrates for most goldfish owners and their goldfish. Gravel is a possibility, but small pieces of gravel can be eaten by some fish, so you will need to keep an eye out for this.
Plants
Goldfish like to nibble at a lot of plants, so adding some goldfish-friendly species is generally considered a good idea. However, this same habit also means that you should avoid putting synthetic or plastic plants in because the fish might still try and eat them.
Lighting
Izumo Nankin Goldfish do need light, but not too much. You can add LED lights to provide daytime light. LED lights last for years, don’t encourage bacterial and algal growth, and provide ample light for goldfish species.
Filtration
You will need a water filter which will help prevent algae and will also help clear out some of the muck and debris caused by the Izumo Nankin. You should also commit to cleaning the tank out every 2 weeks to ensure a clean living environment for your fish.
Are Izumo Nankin Goldfish Good Tank Mates?
Izumo Nankins make good tank mates for any placid fish. They won’t attack the other fish. They won’t try to nibble fins and they won’t bully other species. The only concern when housing Nankins with other fish is for the Nankins themselves. They are very placid which means they can be easily bullied by bigger fish.
Avoid putting them in a tank with aggressive fish or those that are prone to nibbling on tankmates. They do especially well with other species of goldfish. When housing this species with any other fish, always consider the size of the tank and how much room the fish collectively require.
What to Feed Your Izumo Nankin Goldfish
It is best to feed Izumo Nankin a diet of flakes or pellets, which are readily available from the pet store. You can add some natural plants to the tank and the fish may occasionally nibble at these, too. Follow the instructions on the food packet to ensure that you feed an appropriate amount. Feeding too much can lead to overfeeding, but it can also cause the water to get dirty much quicker as any food that is not eaten is left in the water.
Keeping Your Izumo Nankin Goldfish Healthy
Ensure that you have an adequately-sized tank, ideally offering 20 gallons per fish and that your setup includes some day lights and a reasonable water filter. You will need to monitor the pH value, temperature, and the gravity of the water to ensure that it meets ideal requirements. Feed a suitable food. Start by following the instructions on the food packaging but monitor how much your fish eats in approximately 2 minutes and adjust future feeding levels to this amount.
Clean the water every 2 weeks to get rid of leftover food and other dirt and debris.
Breeding
According to some reports, the Izumo Nankin is difficult to breed because the young rarely survive. However, others have had considerable success at breeding Nankins. You will need to separate males and females and then ensure that they have ideal tank conditions to enjoy the best chance of breeding success.
Are Izumo Nankin Goldfish Suitable For Your Aquarium?
Izumo Nankins are placid fish that are relatively easy to care for, except that you will have to regularly clean the tank out and ensure that the water conditions are ideal and that the fish have ample space. They can be kept with other fish, and do especially well when kept with other placid goldfish species.
However, the Nankin is rarely found outside Japan, so whether or not the fish is suitable for your tank may be irrelevant. Although inexpensive to buy, the cost will be hugely inflated if you have to pay to have the fish shipped over from their home country.
Featured Image Credit: Noheaphotos_Shutterstock
