Ranchu Goldfish

The Ranchu Goldfish is often referred to as the “King of Goldfish” due to its refined appearance and popularity among enthusiasts. This dorsal fin–less variety is known for its rounded body, curved back, and prominent head growth (wen). Ranchus have a smooth, flowing silhouette and a graceful, waddling swimming style that sets them apart from other fancy goldfish. They are available in a range of colors including red, white, red-white, black, and calico.

Ranchu Goldfish (Carassius auratus) Description The Ranchu Goldfish is often referred to as the “King of Goldfish” due to its refined appearance and popularity among enthusiasts. This dorsal fin–less variety is known for its rounded body, curved back, and prominent head growth (wen). Ranchus have a smooth, flowing silhouette and a graceful, waddling swimming style that sets them apart from other fancy goldfish. They are available in a range of colors including red, white, red-white, black, and calico. Water Parameters Temperature: 18°C – 24°C pH: 6.5 – 7.5 Hardness: 5 – 15 dGH Ammonia/Nitrite: 0 ppm Nitrate: Below 20 ppm Stable and clean water is essential, as Ranchus are sensitive to poor water quality. Care & Maintenance Ranchu Goldfish require moderate to advanced care due to their body structure: Minimum 75–100 liters tank for a single fish Strong but gentle filtration (avoid excessive current) 25–30% weekly water changes Feed high-quality sinking pellets, along with vegetables and occasional protein foods Use smooth substrate (fine sand preferred) and avoid sharp décor Their lack of dorsal fin makes them weaker swimmers, so a calm environment is important. Behaviour & Temperament Extremely peaceful and social Slow swimmers with a gentle, waddling motion Easily outcompeted during feeding Thrive in groups of similar fancy goldfish They are calm, interactive, and spend most of their time exploring the lower levels of the tank. Compatibility Best kept in fancy goldfish-only aquariums with other slow-moving varieties that share similar needs. Suitable Tank Mates Ranchu Goldfish Oranda Goldfish Ryukin Goldfish (calm individuals) Bubble Eye Goldfish Fantail Goldfish Choose tank mates that are gentle and not overly competitive. Tank Mates to Avoid Fast swimmers like Common and Comet Goldfish Fin-nipping species (Barbs) Aggressive fish such as Cichlids Plecos (may attach and cause injury) Very active or territorial species These can stress or injure Ranchus and outcompete them for food. Pro Tips Feed sinking pellets to help prevent Swim Bladder Disorder Maintain pristine water quality to avoid infections Avoid strong currents—Ranchus prefer calm water Do not overcrowd the tank Monitor wen growth for signs of Bacterial Infection Provide a stress-free, stable environment The Ranchu Goldfish is a premium and elegant fancy goldfish, prized for its unique body shape and calm demeanor. With proper care and a peaceful setup, it becomes a true centerpiece in any high-quality goldfish aquarium.