Origins and Classification
- Scientific Name: Carassius auratus (Ryukin variety)
- Family: Cyprinidae
- Origin: Developed through selective breeding in Japan, originating from the Wakin goldfish line. Known for their humped back and deep, rounded body, Ryukins have been popular for centuries in ornamental goldfish keeping.
- Popularity: Highly valued for their distinctive hump, flowing fins, and vibrant colors, making them a standout choice for fancy goldfish lovers.
🎨 Appearance
- Color Variations:
- Red, orange, white, calico, red-and-white, chocolate, and sometimes tricolor patterns.
- Structure:
- Prominent shoulder hump behind the head.
- Deep, egg-shaped body.
- Long or short flowing fins depending on the variety, often with a double tail.
- Size:
- Typically 6–8 inches (15–20 cm) in indoor tanks.
- Can reach 10 inches or more in ponds.
- Lifespan: 10–15 years, sometimes longer in large, clean environments.
🏡 Tank Requirements
- Tank Size: Minimum 40 gallons for one Ryukin; add 20 gallons per additional fish.
- Water Parameters:
- Temperature: 65–75°F (18–24°C)
- pH: 6.8–7.8
- Hardness: 5–15 dGH
- Lighting: Moderate.
- Substrate: Smooth gravel or sand — avoid sharp decor.
- Habitat Setup:
- Provide wide swimming areas due to their round body shape.
- Add hardy plants (Java Fern, Anubias, etc.).
- Use gentle filtration — strong currents stress fancy goldfish.
🍽️ Diet
- Type: Omnivorous.
- Foods:
- High-quality goldfish pellets (preferably sinking).
- Frozen/live foods: bloodworms, brine shrimp, daphnia.
- Fresh veggies: peas (deshelled), spinach, lettuce.
- Feeding Tips:
- Feed 2–3 small meals per day.
- Avoid floating foods to reduce buoyancy issues.
🤝 Behavior and Compatibility
- Temperament: Peaceful, friendly, active for a fancy goldfish.
- Tank Mates:
- Best with other fancy goldfish (Oranda, Fantail, Ranchu, Telescope, Lionhead).
- Avoid slim-bodied fast swimmers like Comets or Shubunkins.
- Grouping: Great in pairs or small groups of fancy goldfish.
- Behavior: Graceful swimmer with charming, relaxed personality.
💡 Care Notes
- Requires excellent filtration due to goldfish waste levels.
- Perform weekly 30–40% water changes.
- Avoid overcrowding — Ryukins need space.
- Their humped back does not indicate sickness — it is a signature feature of the breed.
- A healthy Ryukin adds beauty, color, and character to any coldwater aquarium or pond.
