Goldfish behaviour can vary widely!
As goldfish are housed in a variety of environments, and because their behaviour can be conditioned by their owners.
The common misconception that goldfish only have a three-second memory has been proven completely false. In fact, scientific studies done on the matter have shown that goldfish have strong associative learning abilities, as well as social learning skills.
Goldfish are even able to distinguish between different humans. It is quite possible that owners will notice the fish react favourably to them (swimming to the front of the glass, swimming rapidly around the tank, and going to the surface mouthing for food) while hiding when other people approach the tank. Over time, goldfish should learn to associate their owners and other humans with food, often “begging” for food whenever their owners approach.
Common goldfish are also very social, and like to live, swim and play in groups.
During the winder it’s completely normal for goldfish to become sluggish, stop eating and stay at the bottom of the pond or tank. They’ll become active again when spring rolls around.
Goldfish Breeding
Goldfish lay adhesive eggs that attach to aquatic vegetation. The eggs hatch within 48 to 72 hours, releasing fry with the appearance of “an eyelash with two eyeballs”.
Within a week or so, the fry begin to look more like a goldfish in shape, although it can take as much as a year before they develop a mature goldfish colour; until then they are a metallic brown like their wild ancestors.
In their first weeks of existence, the fry grow remarkably fast – an adaptation born of the high risk of getting devoured by the adult goldfish (or other fish and insects) in their environment.
Goldfish can only grow to sexual maturity if given enough water and the right nutrition. However if kept well, they may breed indoors. Breeding usually happens after a significant change in temperature, often in spring.
Eggs should then be separated into another tank, as the parents will likely eat any of their young that they happen upon. Dense plants or a spawning mop can be used to catch the eggs.
Most goldfish can and will breed if left to themselves, particularly in pond settings. Males chase the females around, bumping and nudging them in order to prompt the females to release her eggs, which the males then fertilize.
Due to the strange shapes of some extreme modern bred goldfish, certain types can no longer breed among themselves. In these cases, a method of artificial breeding is used called “hand stripping”. This method keeps the breed going, but can be dangerous and harmful to the fish if not done correctly.