Are you new to the world of Ranchu Goldfish and feeling a bit lost? Not sure about how to take care of them or worried they might get sick?
Don’t worry, we’ve got you covered with this detailed guide made just for fish keepers like you. We’ll show you how to make your Ranchu Goldfish not just survive, but really do well in their watery home. Let’s make sure your fish are as happy as can be!
Introduction to Ranchu Goldfish
People often call the Ranchu goldfish the “king of all goldfish.” And it’s easy to see why when you look at how special and pretty they are.
They belong to a special group of goldfish called “fancy goldfish.” These fish are famous for looking really unique and interesting. While regular goldfish can be found in the wild, fancy goldfish like the Ranchu have been specially bred for a long time to look the way they do.

What makes the Ranchu goldfish really special is its long history. Most fancy goldfish come from China, but Ranchu goldfish actually started in Japan in the 1600s. If you know a lot about goldfish breeding, you might notice some features that show off its Japanese background.
China didn’t even know about Ranchu goldfish until much later when keeping fish as pets became popular there. After that, these amazing fish became loved all over the world. Now, people everywhere enjoy having them in their tanks. They’re a big favorite, and if you ever get the chance to take care of one, you’ll quickly see why everyone likes them so much.
Ranchu Goldfish Appearance and Characteristics
Ranchu goldfish are really unique fish that stand out from other freshwater fish. If you’re looking for a fish with a special look, the Ranchu goldfish is a great pick.
One thing that’s really different about Ranchu goldfish is their shape. They don’t look much like the carp they come from. Their bodies are round and plump, kind of like an egg.
Another thing that makes them special is that they don’t have a fin on their back. This makes their back curve up, which adds to their round shape.

Their tail is also something to look at. It starts close to their body and then fans out into a double tail that flows beautifully in the water. It kind of looks like they’re dancing.
On top of their head, Ranchu goldfish have a fleshy bump that looks like a crown. This covers not just the top of their head but also goes around their gills and cheeks. If you’ve seen a lionhead goldfish, it’s similar but even more noticeable. It feels a bit like a ripe raspberry.
When it comes to color, Ranchu goldfish come in all sorts. Some are the classic gold color, but you can also find them in white, black, and even mixed colors like calico. Every Ranchu goldfish looks a little different, which makes them extra special.
Ranchu Goldfish Size
How big do Ranchu Goldfish get? Ranchu goldfish come in a nice range of sizes. A grown-up Ranchu usually gets to be about five to eight inches long. This size works well for different types of fish tanks, giving you some options on where to keep them.
Ranchu Goldfish Lifespan
So, how long do ranchu goldfish live? If you take good care of a Ranchu goldfish, it can live for eight to 15 years. But you should know that how long they live really depends on how well you take care of them.

Because they’ve been specially bred for so long, Ranchu goldfish can get sick more easily than other fish. You have to be really careful about keeping their tank clean and giving them the right food.
If their tank is dirty or they don’t eat well, they might not live very long. So it’s really important to keep their home clean, check on their health, and feed them the right food to make sure they live a long, happy life.
Ranchu Goldfish Care
Ranchu goldfish aren’t super hard to take care of, but they do have certain needs that are really important for keeping them healthy and happy. Because they’ve been specially bred, they’re more likely to have health issues. So, you need to be extra careful in looking after them.

By following the tips below, you can make sure your Ranchu goldfish have a great home where they can really thrive.
Ideal Ranchu Goldfish Tank Size
Ranchu goldfish are pretty calm, so they don’t need a huge tank to swim around in. When they’re young, you can start them off in a 10 gallon tank. But as they grow, you’ll want to move them to a bigger tank, at least 30 gallons. If you have the room, a 55-gallon tank is even better for just one Ranchu.

A big tank isn’t just for show; it’s really important for the fish. A small tank can limit how much they grow and make them more stressed and sick. So, giving them enough room is key to keeping them healthy and happy.
Water Parameters for Ranchu Goldfish Care
Even though Ranchu goldfish aren’t from the wild, their carp ancestors were. So, try to make their water like the cool rivers in Asia where carp are happy.
- Water temperature: Keep it between 65 and 75 degrees Fahrenheit.
- pH levels: Aim for a neutral pH between 7.0 and 8.0.
- Water hardness: Keep it between 5 and 19 DH.
Ranchu goldfish like their water to have plenty of oxygen, even if they don’t like fast currents. Check the water often to make sure it stays the same.
Setting up the Perfect Tank for Ranchu Goldfish
Ranchu goldfish can adjust to different setups, but they’ll be happier and healthier if you set up their tank the right way.
- Use sand or smooth pebbles on the bottom. Ranchu goldfish like to move things around, so don’t worry if they mess up your design.
- Pick sturdy plants that won’t get torn up easily. Good choices are anubias, java fern, and java moss. Attach them to big rocks so they stay put.
- Make sure to have a good filter. Ranchu goldfish make a lot of waste, so a strong filter is a must-have.

Common Diseases of Ranchu Goldfish and Prevention Tips
Ranchu goldfish are pretty, but they can get sick easily. Some of this is because of their genes, but you can help keep them healthy.
- Keep their tank clean and change the water often. This helps prevent many common diseases.
- Watch out for signs of sickness like Ich, velvet disease, and fin rot. For example, Ich shows up as white spots and can happen if the fish get stressed. But you can treat it if you catch it early.
Feeding and Diet for Ranchu Goldfish
A well-fed Ranchu is a happy Ranchu! They like to eat both plants and meaty foods.
- Use good-quality flake or pellet food as their main diet.
- Add in treats like tubifex worms, bloodworms, and other insect foods. You can give them live, frozen, or freeze-dried versions, but many people avoid live foods because Ranchus swim so calmly.
Behavior and Temperament of Ranchu Goldfish
Ranchu goldfish are super chill and fun to watch. They don’t dart around the tank really fast. Instead, they swim slowly, making their big tails wave around like they’re dancing. This is really calming to watch and one of the neat things about these fish.
They’re also pretty curious and like to look around their tank. You might see them nudging decorations or even moving plants or taking a little bite of a leaf. They’re not being naughty; they’re just exploring in a gentle way.
So, if you’re after a fish that’s peaceful and fun to look at, Ranchu goldfish are a great pick. Whether you’re new to fish-keeping or you’ve been at it for years, you’ll love having this calm and beautiful fish as your pet.
Suitable Tank Mates for Ranchu Goldfish
Ranchu goldfish are really easygoing and get along with other fish. But, because they’re so calm, you have to be careful they don’t get bullied by meaner fish.

Keep them away from aggressive types like Cichlids and Oscars. Also, watch out for small fish that like to nip fins, as they might go after the Ranchu’s beautiful tail.
So, what kind of fish make good friends for a Ranchu? Pick ones that like cold water and are also easygoing. Here are some good choices:
- Lionhead Goldfish: They’re fancy like Ranchus and get along really well with them.
- Bubble Eye Goldfish: These guys are easygoing and have funny looking eye sacs.
- Pearlscale Goldfish: They have unique, round scales and are super friendly.
- Black Moor Goldfish: These fish are dark-colored and also pretty calm.
- Guppies: These small, colorful fish are peaceful and won’t bother your Ranchu.
- Mosquitofish: They’re chill and help keep away mosquitos by eating their larvae.
- Zebra Danios: These fish have stripes and are active but won’t bully your Ranchu.
- Platies: They’re colorful and easygoing, making them good tank mates.
- Chinese High Fin Banded Sharks: Despite the scary name, they’re peaceful. But they get big, so you’ll need a big tank.
- Dojo Loaches: These guys hang out at the bottom of the tank and are fun to watch.
Breeding Ranchu Goldfish: Tips and Considerations
Breeding Ranchu goldfish is an endeavor of patience and precision. Knowing the sexes of the fish is your first step, and that can be a bit tricky. Males and females look pretty similar, but as they get older, males will develop tiny bumps called tubercles on their gills and faces.


Here’s how experienced breeders typically go about the breeding process:
Preparing a Breeding Tank
Your first task is to prepare a separate breeding tank with similar water conditions to your main tank. To help with the egg scattering, include fine-leaf plants. Breeding nets and other tools can also protect the fragile eggs.
The Spawning Process
When the fish are ready to spawn, the female will lay a large number of eggs—sometimes in the thousands! As the female swims, she releases sticky eggs that attach to plants and other surfaces in the tank.
Post-Spawning Care
Right after spawning, it’s crucial to move the adult fish away from the eggs. Ranchus don’t have strong parental instincts and might eat their own eggs if given the chance.
Hatching and Initial Care
The eggs typically hatch in about 2 to 3 days. The newborn fry will feed off their own yolk sacs for a few more days before swimming freely. To ensure their safety, keep them separate from the adult fish.
Nurturing the Fry
To give the fry the best start, house them in a large tank or even a pond. Their initial diet should consist of fine powdered or liquid fry food. As they grow, you can gradually introduce them to high-protein foods like baby brine shrimp and infusoria.
Growth Phases
Ranchu fry grow quickly in the first few months but slow down as they mature, averaging about an inch of growth per year thereafter.
Conclusion
In summary, Ranchu goldfish are a captivating blend of grace, beauty, and unique features. They may not demand overly complex care, but they do ask for your attentiveness and diligence. Given their vulnerability to health issues and their refined physiques, even a small lapse in care can have adverse effects.
However, don’t let this deter you. With proper care and commitment, creating a flourishing habitat for these aquatic marvels is well within reach. The reward? A tranquil, captivating Ranchu that enriches your life and brings a touch of serenity to your home.
We hope this comprehensive guide serves as a helpful resource on your fishkeeping journey. At DryWash Aquarium, our mission is to transform every aquarium into a thriving aquatic sanctuary. For more expert tips and insights, feel free to delve into our extensive collection of articles.
Happy fishkeeping, and may your Ranchu goldfish live a long, vibrant life!