As a member of the carp family, the Ranchu Goldfish is generally quite hardy. It will do well in 30 gallon aquariums or larger, as well as backyard garden ponds of 180 gallons or more. In addition to a fine gravel bottom or well-rounded river rocks, the Ranchu Goldfish will appreciate hardy, cold water plants. Keep in mind that goldfish are diggers and will scatter the fine sand onto leaves, injuring thin and less hardy plants.

There appears to be a definite courtship ritual when goldfish breed. Breeding often results in up to 1,000 eggs, with fry hatching in five to six days. They should be fed small pieces of live or prepared foods designed for egg-laying fish.

Goldfish are omnivores and will eat all types of dried and live foods. However, limit protein intake to 30% of the diet. Goldfish flake or pellet food will provide these fish with the proper nutrition.