Goldfish have good memory lasting many months. Many people wrongly believe that they have a memory lasting only a few seconds.
Experiments conducted by researchers have shown that Goldfish can be trained to press a lever to get food. In other experiments, goldfish had been trained to respond to a sound. The fish were fed food whenever the sound was played.
The goldfish were able to remember the relation between the sound and food many months later.
Goldfish are very intelligent among aquarium fish. They can also be trained to perform tricks such as passing through a hoop by rewarding them with food.