The fancy goldfish (Carassius auratus) is a freshwater aquarium fish which is also known as common goldfish.  It is native to eastern Asia which is distributed from Siberia to China and it has now spread around the world.  It inhabits rivers, lakes, ponds and ditches with vegetated stagnant or slow-flowing water.

Fancy Goldfish’s Overview

Carassius auratus has an elongated, stocky body with broadly triangular head. The caudal fin is moderately forked with 17-19 soft rays and the edge of the dorsal fin is slightly concave. The snout is longer than eye diameter.  It possesses a long dorsal fin with 15 to 21 soft rays while anal fin contains 2-3 spines and 4-7 soft rays. The lateral line is complete with 25–31 scales in a lateral series. Carassius auratus has no barbels on the upper jaw and lack scales on the head with exceptionally large eyes. The anal fin of the male is concave whereas on the female it is convex. The pelvic fins are short, broad and thoracic. It varies in color from gold to olive green or even creamy white. It feeds mainly on plankton, benthic invertebrates, plant material and detritus. It tolerates high levels of turbidity, temperature fluctuations and low levels of dissolved oxygen. The fancy goldfish lays eggs on submerged vegetation. Females spawn multiple times during the spawning period. It grows up to 45 cm in length and can live up to 41 years.

Scientific Name: Carassius auratus

English Name: Common Goldfish

Origin:  China, Japan

Adult Size: Usually 3 to 5 inches (8 – 13 cm)

Behavior: Very peaceful

Tank Level: All levels of the tank

Minimum Tank Size:  25 gallons

Diet: Omnivore

Breeding: Egg layers

Care level: Easy

Water pH: 6.0-8.0

Water Hardness: 5° to 20° dH

Water Temperature: 65.0 to 72.0° F

Water Movement: Moderate

Lighting: Moderate – normal lighting

Lifespan: 10 – 41 years

Background of fancy goldfish

Crassius auratus was first domesticated in China. It was bred about 1000 years ago in China for aquaria, ornamental ponds and as food fish.  According to Dr. Yoshiichi Matsui, a professor of fish culture at Kinki University in Japan, Carassius carassius is the wild version of the fancy goldfish. It belongs to the carp or minnow family, Cyprinidae under order Cypriniformes of Class Actinopterygii. Now many ornamental breeds have developed for aquariums and water gardens throughout the world.

Housing fancy goldfish

The Fancy goldfish is a favorite fish for aquarium hobbyist. 25 gallons or larger aquarium is recommended to keep fancy gold fish. It is usually very hardy fish and it can live in temperatures which range from 65.0 to 72.0° F. The tank should have pH and hardness which ranges from 6.0 to 8.0 and 5 to 19° dGH respectively. This fish swims in all areas of the aquarium. They should be kept in groups of 5 or more individuals. It does usually better when it is kept with other goldfish.  Some good tank mates for fancy goldfish are the Chinese Blue Bitterling and the Northern Redbelly Dace. Other potential tank mates include white cloud mountian minnows and similar cold water species.

Good filtration especially biological filtration is required for maintaining the water quality of the aquarium. Because this filtration system removes detritus, excess foods and wastes which help to keep the tank clean and maintain the general health of the fish in aquarium. The tank should be decorated with gravel substrate that helps to create a natural and comfortable environment for your fish. Aquarium plants are the best choice of aquarium decor for your fancy goldfish. In these cases, artificial plants make a good substitute and silk plants are safer than plastic plants. A regular weekly water change is strongly recommended to keep your fish healthy. Snails can be added as they reduce the algae in the tank that helps to keep the tank clean.

Feeding fancy goldfish

The fancy goldfish is omnivores and in wild condition it mainly feeds on plants, insects such as mosquito larvae, small crustaceans, zooplankton, benthic invertebrates and detritus. In captive condition it gladly accepts most fish foods including flakes live and freeze dried varieties. It should be fed a balanced diet that includes freeze dried Tubifex worms, mosquito larva, bloodworms, Daphnia, brine shrimp and vegetation such as boiled peas and lettuce, aquatic plants such as duckweed, azolla or salvinia and algae. Feed should be supplied two or three mouthfuls per fish twice a day.

Breeding fancy goldfish

It is easy to breed in aquarium. It reaches sexual maturity for breeding at the age of one year. During breeding season, the abdomen of the female becomes fuller and heavier. The male develops ‘breeding tubercles’ on the gill operculum and along the front rays of their pectoral fin and sometimes on the head. These ‘breeding tubercles’ are a white pimple roughly the size of a pin head. The fish should be kept in separate tanks before breeding. They are actually capable of breeding in the early morning light when the temperature of the water is between 50-78.8 0F but the optimum temperature is 68 0F. The female lays 500 to 1000 eggs on plants on the bottom of the tank and eggs hatch in 48-72 hours. The optimum temperature for the eggs to hatch is 69.8 0F. The hatched fry are very small and it grows in size rapidly and after 12 months it shows adult coloration.  After spawning the parent fish should be removed to prevent them eating the eggs. The fry need to be fed sufficient food such as infusonia and brine shrimp for twenty minute period and any uneaten food should be siphoned off.

Sexing fancy gold fish

It is nearly impossible to sex a fancy goldfish accurately less than 1.5 – 2 years of age.  The only way to sex your goldfish is during the breeding season. Males have small white spots called tubercles around their gill areas when ready to spawn. Females may have rounder convex vents while males have thinner concave vents.

Fancy Goldfish for sale & Where to buy

This popular aquarium fish are available for you to choose. But good quality fish is scarce. Unable to buy good quality fancy goldfish is one of the major frustrations for goldfish lovers.  You can choose from a wide range of selection and price that fit your budget. See below online vendors to buy your favorite fish that I would recommend from.