A lot of people misconstrue the fish’s uncontrolled eating to be a sign of lack of intelligence. Nothing could be further from truth! Goldfish can actually recognize their owner and have even demonstrated their learned ability to beg for food when the owner come near the aquarium. They may also exhibit recognition by coming close to the glass wall or circle around the surface of the water. They will also show fear of strangers by hiding.
Goldfish have also been noticed to show social behavior. A new fish in the tank may be chased or nipped at. After a while though, fishes might show schooling behavior. They also exhibit similar feeding habits when they have been living together for some time.
Goldfish also seem to stop treating humans as threats once they have been amidst them for some time. So much so that you can actually feed them from your hand! Try this trick with soaked pellets. First set a time of the day. Everyday at the same time do this the same way for at least a month.
Hold the food above the water surface when you remove the cover. The fish will begin to rise occasionally ; then release the food only when it does so. Don’t touch the surface of the water yet, you will scare the fish. As the fish get used to this daily ritual, they will rise higher and higher until they begin to hit the surface and gasp. Now try to drop the pellets into their gasping mouths. Next, start lowering your hand little by little. Do this everyday till you reach the surface of the water and then slowly take it a little under the surface and Voila! You have the fish eating out of your hand!