The words Dog Breed Info with the letter D inside of a black paw print

Goldfish

Information and Pictures

Two large orange gold fish and one blue kissing fish are wading at the front of a glass aquarium. The tank has blue gravel and a tan rock with algea on it.

Two goldfish and one kissing fish

Scientific Name

Carassius auratus

Type

Cyprinids

Family

Cyprinidae

Subfamily

Cyprininae

Other Names
  • Gold Fish
Minimum Tank Size

Small Goldfish: 10 gallons
Large Goldfish: 40 gallons

Tank Level

Mid-dweller, but does visit all levels.

Care

Easy

Behavior

Peaceful schooling fish. Messy, produces a lot of waste. Should have some type of extra aeration, as they have high oxygen requirements. Makes a great bottom scavenger. May up-root plants.

Compatibility

Gets along well with other non-aggressive fish. Does best with other goldfish, but can live with other peaceful fish species. Goldfish put off a lot of ammonia. While goldfish can handle a higher level of ammonia, this level can kill other types of fish and must be taken out of the water. If you are going to keep goldfish with other fish species, be sure to monitor your ammonia levels. Goldfish do not like ammonia and prefer a clean, filtered tank. Great social, community fish, however, since they prefer colder temperatures, they do best with other goldfish that can also live in these cooler temps.

Life Span

20 years

Size

Adults can reach up to 23 inches (59 cm).

Aquarium

Likes to eat live plants, so fake plants are ideal if you do not want your plants eaten. Gentle circulation. While they can live in a small bowl they do best with a larger aquarium with a filter system. They do not need a heater in an indoor aquarium.

Water Chemistry

Freshwater

pH

6.0 - 8.0

Hardness

dH: 5 - 19 (soft to hard)

Temperature

Considered a cold-water fish. Ideally they like 50° - 70° F (10° - 21° C). A goldfish can live in waters just above freezing. There are many goldfish that live in outside ponds, and so long as the water does not freeze, they can survive the winter. They do not particularly like tropical temperatures, and will not be as healthy, but they can survive.

Feeding

Omnivore (animals that eat both meat and vegetables). Flake foods (green flakes), Does best on a special goldfish diet, which can be purchased at your local pet store. They do not tolerate tropical fish food very well, as they do not have stomachs. Their food is absorbed as it travels through their intestines. Goldfish food has a higher alkaline content than tropical fish food. Feed flake foods every day and give brine shrimp (either live or frozen), tubifex worms, blood worms and daphnia only as a treat. Freeze-dried foods are recommended over live foods to avoid introducing bacteria and parasites into the tank.

Sexing

During the breeding season males develop white pimple-like bumps called breeding tubercles on their gill covers and on the leading edge of the pectoral fins. These are used for stimulating the female to release her eggs. Pregnant females develop a deeper body when they are full of eggs (roe), and they also have a larger vent, located right before the anal fin.

Breeding

Egg layer

Origin

China, parts of Siberia

Extras

The most common cause of death in goldfish is overfeeding. Their colors depend on the environment they are raised. For example, pond and river goldfish are usually duller in color than the goldfish raised in a bright fish tank.

Three large goldfish, a blue kissing fish and a black pleco. Two of the goldfish are orange and one is orange and white. They are inside of a fish tank. There is a CRT TV in front of the Aquarium and behind it is a plant on a stand

Three goldfish and a pleco, which is an algae eater. The pleco is the black fish on the bottom of the tank.