The common goldfish known as Carassius Auratus, Auratus means “gold” and this is what gave the goldfish its name. The common is the simplest variation of all goldfish breeds. The goldfish are part of the Cyprindae family of fish which also includes koi, carp, and minnows. The common goldfish is the fish that most resembles its carp ancestors. Goldfish have been raised by humans for over a thousand years and genetically modified to produce the breeds we see today. Originally, Carp were bred for meat and a genetic anomaly would occur occasionally and yield the gold color, this gold color was considered special and those colored fish were saved in a “mercy pond”. This led to breeding of special colors exclusively and eventually the keeping of goldfish as pets.
Today Common Goldfish come in a variety of colors, ranging from red, yellow and orange to bronze and black.
Common Goldfish are sometimes confused with the Comet Goldfish. However, the comet has much longer fins and a longer and more deeply forked tail fin. The common variety also has a more blunt and rounded head.
Temperament and care
The Common Goldfish is one of the hardiest species of freshwater aquarium fish. It’s therefore an ideal fish for beginners. However, despite common thinking, a goldfish bowl is not a suitable home for your fish.
Commons can tolerate quite low water temperatures and can even survive for brief periods in frozen-over ponds, provided they have enough oxygen and food. They can also be raised with koi, but should not be kept with slower varieties of goldfish, as they will out-swim and out-compete their slower counterparts for food. Goldfish are naturally social creatures and do better with aquarium mates that are able to keep up with common.
They’re certainly not finicky eaters and will devour almost any type of food provided. They are active foragers and will keep scouring the bottom of the aquarium for food. This should be taken into account when aquascaping and deciding on a filtration system. Goldfish produce a significant amount of waste so an adequate filtration system is a must. They also disturb the bottom of their aquarium or pond due to them being foragers and this can cause murky water if not filtered appropriately. If they are kept good care of, then a Common Goldfish can live for several years.
Breeding common goldfish
Given adequate space and food, goldfish will spawn quite readily and prolifically. In fact, it is quite ordinary for common goldfish to overpopulate a pond within a few months of being introduced!
In the wild, goldfish usually spawn during warmer months of the year. Breeding can therefore be induced by lowering and then gradually raising the water temperature of a pond or aquarium. Goldfish devour their own young and eggs, so spawning mats or a heavily planted aquarium (where fry can hide) is recommended if you want the fry to survive.
Choosing common goldfish
When buying your fish, it’s important to pay attention to the basics, such as health and deformities.
The ideal characteristics of a common goldfish include a body depth of 3/8 of the body’s length and a tapered off mouth, which leads smoothly into the curve of the back and stomach.
The fins of the common goldfish should be single and slightly rounded, except for the pectoral and pelvic fins. All fins should be rigid and the tail fin should be rounded and less than 1/3 of the length of the body.