The Ultimate Ranchu Goldfish Care Guide: From Tank Size to Lifespan

Dr. Mollie Newton
Published by Dr. Mollie Newton PHD| Senior Editor
Last updated: May 26, 2024
Review Process and Evaluation Criteria
We conduct hands-on testing for all the products highlighted in our reviews and guides. Through anonymous product ordering and involving an independent team of testers, we gather direct experience to offer recommendations backed by data.

Adored by aquarium enthusiasts globally for its unique appearance and gentle nature, the exquisite Ranchu Goldfish is truly a sight to see. Caring for these mesmerizing fish requires knowledge of their background, needs, and behavior to ensure their well-being and happiness. Come along as we dive into the realm of Ranchu Goldfish, exploring their origins, recognizing their distinct features, and offering crucial care tips to help you cultivate the ideal habitat for your aquatic friends. Let’s set off on this enchanting adventure together!

Key Takeaways

  • Ranchu Goldfish is a distinct and highly sought-after fancy goldfish variety renowned for its captivating appearance, gentle temperament, vibrant colors, and well-developed wen.
  • Creating a spacious tank with the right temperature, filtration, and environment is essential for providing a healthy home for your Ranchu Goldfish.
  • Regular tank maintenance & prompt action in case of illness are key to preventing & treating common diseases in Ranchu Goldfish. Purchase from reputable sources to ensure quality.

Ranchu Goldfish: A Unique Fancy Goldfish

Albino Ranchu

The Ranchu Goldfish is a remarkable ranchu fancy goldfish variety known for its captivating appearance and gentle temperament. With their bulbous bodies and heads, high-quality Ranchu Goldfish boast vibrant colors, well-developed wen, and balanced body proportions. Their serene character makes them ranchu goldfish suitable tank mates for other peaceful fish with similar water requirements, such as Lionhead Goldfish and Telescope Goldfish.

These beautiful fish are freshwater fish, descending from the wild carp, and have been selectively bred over the years, creating numerous other species. Ranchu Goldfish, in particular, are highly sought-after by goldfish enthusiasts for their unique characteristics and intriguing history.

Origins and History of Ranchu Goldfish

Ranchu Goldfish Plate

Ranchu Goldfish originated in China. During the 1800s, they were further developed in Japan. Japanese breeders introduced a wide, significantly curved back, a spread tail fin, and an absence of dorsal fin, creating the distinct appearance we appreciate today. Ranchu Goldfish, sometimes referred to as buffalo head goldfish due to their bulbous head, have become one of the oldest and most sought-after fancy goldfish varieties.

The Ranchu Goldfish’s development has significantly impacted its popularity in the fancy goldfish hobby. This fascinating history has contributed to the growth of Ranchu Goldfish breeding, with enthusiasts and breeders worldwide continually striving to perfect their appearance and characteristics.

Identifying Ranchu Goldfish: Appearance and Characteristics

Three Ranchu on Display

Ranchu Goldfish are characterized by:

  • Metallic scales
  • Broad head with a fleshy wen
  • Wide back with a highly curved contour shape
  • Range of colors, with the most common combinations being red and white or gold and white
  • Unique tail fin shape, often almost horizontal

All of these features add to their charm and beauty in the water.

Their swimming style is also quite distinctive, as they gracefully oscillate their tail back and forth, creating a mesmerizing motion. Ranchu Goldfish’s unique appearance and swimming style set them apart from other fancy goldfish varieties, making them a prized addition to any aquarium.

Head Growth (Wen)

The wen, a raspberry-like structure on the Ranchu Goldfish’s head, is a fascinating and defining feature of this fish. The biological purpose of the wen remains unclear, but it is believed to be made up of adipose tissue, which is used as a store of fat in many animals. This unique feature can sometimes cover the fish’s eyes and affect their vision and agility, making proper care essential to maintain their well-being.

Maintaining a clean tank environment and a balanced diet is fundamental to the overall health and longevity of Ranchu Goldfish with wen growth. A suitable tank size and carefully chosen decorations contribute significantly to the fish’s comfort and help prevent damage to the wen.

Curved Back and Splayed Tail Fin

The features that distinguish Ranchu Goldfish from other goldfish varieties are:

  • Curved back
  • Splayed tail fin
  • Prominent arch in their back
  • Absence of a dorsal fin
  • Tail fins that point downward or splay outwards

These features give Ranchu Goldfish a hunched appearance and a distinct look.

This unique body structure contributes to the Ranchu Goldfish’s distinctive swimming style, as the tail lobes meet the caudal peduncle at a 45-degree angle, allowing them to swim gracefully and effortlessly despite their compact body and short fins. The curved back and splayed tail fin truly set Ranchu Goldfish apart in terms of charm and beauty.

Caring for Your Ranchu Goldfish: Tank Requirements and Environment

Ranchu Goldfish in Aquarium

A spacious tank fitted with suitable water parameters, filtration, and the right environment is necessary for the health and well-being of your Ranchu Goldfish. Here are some important considerations:

  • The minimum tank size for Ranchu Goldfish is 10 gallons.
  • The recommended temperature range is 65-72°F (18-22°C).
  • Regular water changes are crucial for maintaining good water quality.
  • Proper filtration is necessary to keep the tank clean and remove waste.
  • Appropriate tank conditions, such as providing hiding spots and suitable substrate, are important for the well-being of your goldfish.

By ensuring these factors are met, you can provide a healthy and comfortable environment for your Ranchu Goldfish.

When setting up the tank environment, it’s important to consider the delicate nature of your Ranchu Goldfish. Avoid any sharp or jagged objects that may cause injury to the fish’s fins or body. Additionally, provide well-oxygenated water, as Ranchu Goldfish require a high oxygen content to thrive.

Substrate and Decorations

The right substrate and decorations for your Ranchu Goldfish tank are necessary to prevent injury to the wen and ensure secure anchoring for aquatic plants. Smooth substrates such as aquarium gravel, sand, and pebbles are suitable options for a Ranchu Goldfish tank. Sharp or jagged decorations should be avoided to prevent damage to the fish’s body and delicate fins.

When introducing aquatic plants, ensure they are properly secured in the substrate to prevent the Ranchu Goldfish from consuming the leaves and uprooting the roots. Live plants not only add aesthetic appeal to the tank but also provide hiding spots and help maintain water quality.

Oxygenation and Lighting

Ranchu Goldfish require high oxygen content for their well-being, making oxygenation a vital aspect of their care. An air pump and an air stone are the most suitable equipment for maintaining oxygen levels in a Ranchu Goldfish tank. While lighting is not imperative for Ranchu Goldfish, it can assist in enhancing their colors and supporting live plants in the tank.

It’s important to provide a balanced lighting schedule for your Ranchu Goldfish, as they lack eyelids and require darkness to rest and sleep. LED lighting can be an energy-efficient option that offers the right spectrum for supporting live plants and showcasing the vibrant colors of your Ranchu Goldfish.

Feeding Your Ranchu Goldfish: Diet and Nutrition

Blue Ranchu Goldfish

Ranchu Goldfish are omnivores and require a balanced diet of plant matter and protein, including live food from reputable sources. Feed your Ranchu Goldfish:

  • Nutritionally balanced flakes or pellets specifically formulated for fancy, round-bodied goldfish
  • Frozen or fresh bloodworms
  • Daphnia
  • Tubifex worms
  • Brine shrimp

This will ensure a varied and healthy diet for your Ranchu Goldfish.

When feeding your Ranchu Goldfish, follow these guidelines:

  • Offer an amount of food that can be consumed within two minutes
  • Feed them two to three times a day
  • Remove any uneaten food after feeding sessions to prevent fouling the water and maintain proper water quality.

Live Food Precautions

Live food offers valuable nutrients for your Ranchu Goldfish, but caution is needed as it can carry parasites or bacteria that could infect your fish. Suitable live food for Ranchu Goldfish includes:

  • Brine shrimp
  • Bloodworms
  • Daphnia
  • Tubifex worms

To ensure the live food is free from potential contaminants, it’s crucial to purchase from reliable sources and take proper precautions, such as soaking the food in water before feeding.

By being cautious with live food and providing a diverse diet, you can help maintain the health and well-being of your beloved Ranchu Goldfish, ensuring they thrive with proper ranchu goldfish care.

Choosing Suitable Tank Mates for Ranchu Goldfish

Hagoromo Ranchu

Selecting tank mates for your Ranchu Goldfish requires careful consideration. Choosing similar fancy goldfish types or slow-moving, peaceful fish, like Lionhead Goldfish or Telescope Goldfish, helps avoid competition and stress. Tank mates Ranchu Goldfish are ill-equipped to find food before faster, more competitive tank mates, which could lead to stress and malnutrition.

Avoid pairing your Ranchu Goldfish with fast-moving or slim-bodied goldfish, as this may result in bullying, fin nipping, or resource competition within the tank. By carefully choosing suitable tank mates, you can create a harmonious and stress-free environment for your Ranchu Goldfish to thrive.

Breeding Ranchu Goldfish: Tips and Techniques

Ranchu Goldfish against dark substrate.

The process of breeding Ranchu Goldfish, a type of breeding goldfish, includes:

  1. Distinguishing between males and females. Male Ranchu Goldfish will exhibit tubercles on their gill plates and faces, while females will have no such distinguishing features.
  2. Creating a suitable spawning environment.
  3. Feeding them appropriate fry food.
  4. Males will demonstrate their readiness to breed by exhibiting breeding stars and pursuing the females.

To facilitate the spawning process, follow these steps:

  1. Provide a lush environment with solid surfaces for the eggs to adhere to, such as surface plants and breeding mats.
  2. After a successful spawning, remove the male and female, as they may attempt to consume the eggs.
  3. As the fry develop, provide them with powdered or liquid fry food, suitable for young fish.
  4. Eventually, transition them to high-protein meals such as baby brine shrimp or infusoria, when they are old enough.

Preventing and Treating Common Ranchu Goldfish Diseases

Like other pet fish species, Ranchu Goldfish, common in captivity, can be susceptible to diseases. Maintaining a clean tank and balanced diet can help prevent and treat common ailments. Regular water changes, proper filtration, and appropriate tank conditions are essential to keep your Ranchu Goldfish healthy and disease-free.

Should a disease outbreak occur, it is advised to:

  • Seek advice from a veterinarian
  • Administer the required medication to treat the affected fish
  • Quarantine sick fish in a separate tank to prevent the spread of disease to other tank mates

By closely monitoring your Ranchu Goldfish’s health and taking prompt action in case of illness, you can help ensure their long-term well-being.

Swim Bladder Disease Management

Healthy Ranchu Goldfish

Swim Bladder Disease is a common ailment that affects the swim bladder, a gas-filled organ that assists the fish in controlling its buoyancy. Managing Swim Bladder Disease in Ranchu Goldfish involves maintaining high water quality and adjusting the fish’s diet accordingly.

Starve the fish for 24 hours. After that, offer thawed frozen food, live bloodworms, or a defrosted pea with the skin removed. Providing a balanced diet and ensuring proper water quality can help prevent Swim Bladder Disease and keep your Ranchu Goldfish healthy.

Purchasing Ranchu Goldfish: Availability and Pricing

Ranchu Goldfish are easily accessible in many fish stores and websites, facilitating enthusiasts to include these attractive fish in their aquariums. Prices for non-competing Ranchu Goldfish typically range from $5 to $25, with factors such as:

  • size
  • growth potential
  • breed quality
  • breeding efforts

influencing the price.

High-grade specimens, often used for competition or breeding, can fetch prices of $100 or more. Choosing a trustworthy source is a key factor when buying Ranchu Goldfish to confirm the health and quality of the fish. Remember, investing in a high-quality Ranchu Goldfish will contribute to the beauty and enjoyment of your aquarium.


In summary, Ranchu Goldfish are a unique and captivating fancy goldfish variety that require proper care and attention to thrive. Understanding their origins, appearance, and characteristics, as well as providing a suitable tank environment, balanced diet, and compatible tank mates, is essential to ensure their health and happiness.

With meticulous care and a passion for these charming fish, you can create a thriving aquatic environment that showcases the beauty and grace of Ranchu Goldfish, making them a prized addition to any aquarium.

Frequently Asked Questions

Are Ranchu goldfish rare?

Ranchu Goldfish are rare in the Animal Crossing series, appearing only during certain events such as Fishing Tourney: Elegant Aquarium and Fishing Tourney: Foliage, and they are among the rarest fish spawns in Animal Crossing: New Horizons with a short window of activity from 9 a.m. until 4 p.m. each day.

Do Ranchu goldfish need a heater?

Yes, goldfish need both a filter and a heater in order to remain healthy and have clean water. Goldfish are cold-water fish and need a stable water temperature, so a heater is essential for Ranchu goldfish.

Why is Ranchu king of goldfish?

Ranchu goldfish are highly prized in Japan, with some even selling for hundreds of dollars, and are distinct as they lack any dorsal fin. They have metallic scales and come in a range of colours, making them the deserving ‘King of Goldfish’.

How much does a ranchu cost?

A Ranchu fish can be purchased for only $12.99, making it an accessible and affordable choice for anyone interested in aquariums.

What is the minimum tank size for Ranchu Goldfish?

For optimal health and comfort, it is recommended to keep Ranchu Goldfish in a tank of at least 10 gallons.

You May Also Like