What do you think of this fact?
The goldfish swims its lap around the bowl and is delighted by the same plastic plant every single time. That’s the story behind the three-second memory myth, anyway. It has very little to do with real fish.
At least three months
According to the science magazine How It Works, goldfish memories last at least three months. Researchers have trained goldfish and other fish to swim through mazes, respond to light and sound cues, and show up at the same feeding spot at the same time every day.
Anyone who has ever fed fish knows the drill: the lid barely opens and the whole crowd is jostling at the surface. That’s not a coincidence, it’s learned behavior.
The loudspeaker in the sea
An experiment from Israel shows how long that can last. On a fish farm, researchers played a sound to fish through an underwater loudspeaker for one month, each time together with food. Soon the fish gathered at the speaker on their own whenever they heard it.
Then the researchers released the fish into the open sea. Months later, they played the sound again, and the fish swam back to the speaker. According to Practical Fishkeeping, they remembered it for four to five months.
Bonus fact: In another experiment, goldfish learned to avoid areas of their tank where they had received a mild electric shock. They stayed away for at least 24 hours.
So why does the myth hang on? How It Works suggests a convenient reason: if you believe a fish forgets everything instantly, you feel less guilty about keeping it in a small, empty bowl.
The goldfish knows exactly when dinner is due. And probably who keeps forgetting it.