January 24, 2014

Fun Fish Facts

  • Goldfish are descendants of carp and have their origins in China.

  • There are hundreds of varieties of goldfish found around the world.

  • Goldfish have teeth in their throat called pharyngeal teeth which are used to help them crush their food.

  • Goldfish may grow as long as 23 inches and weigh nearly 7 pounds, although this is rare.

  • Goldfish do not have stomachs. Different parts of their intestines do the job of breaking down food and absorbing nutrients.

  • Goldfish can live up to 30 years—longer than most other aquarium fish.

  • In the 18th century, members of the European aristocracy would remove goldfish from their ponds and place them into decorative bowls for special occasions.

  • A goldfish cannot be reliably sexed until they are at least one year of age.

  • It is easiest to identify the distinguishing features between male and female goldfish during the breeding season. At that time, males develop white, pimple-like spots on their gills. The females’ abdomen becomes enlarged. Another distinguishing feature is the size and shape of the vent located near the anal fin. A male’s vent tends to be narrow, concave and more oval. A female’s vent is more convex and round.

  • Goldfish courtship can create quite a splash in your aquarium! Once the female reaches sexual maturation, she begins to release pheromones. This triggers the male to begin his pursuit by chasing the female around and poking at her stomach. This behavior is often confused with fighting and can become quite aggressive. The male is trying to get the female to release her eggs which are held in the abdomen. It is best to have a planted area in the tank for her to lay her eggs. The female lays up to 500 eggs at a time. Once the eggs are released, the male fertilizes them. Goldfish will eat their own eggs, so it is best to remove them and place them in a different tank.

  • Contrary to popular belief, the goldfish memory span is far beyond three seconds. Goldfish have the capacity to learn and adopt patterns of behavior. Yup, this means you can train your goldfish!

  • A school of fish is known as a "troubling."

  • Goldfish do not blink…because they have no eyelids! And yes, this means they sleep with their eyes open.

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