Goldfish Memory – Just 3 Seconds? Is this True or Just a Myth?

If you’re reading this, you’ve probably had somebody tell you goldfish memory lasts a mere 3 seconds?

A lot of people believe this, but is it true or just a myth?

Goldfish memory - is it 3 seconds? Written beside a white and orange goldfish superimposed across an aquarium background

We’re here to get to the bottom of this and sort the fact from fiction so you can discover, for once and for all, if your goldfish truly has a memory like a sieve or if people have been spreading false information all these years.

Do Goldfish Have Three Second Memories?

The short answer: No, goldfish don’t have a three second memory span. In fact, it’s likely they can remember things for several months, if not more.

If you’ve ever noticed your goldfish waiting for you to feed them at a specific time of day to check the same spots for leftover food, it should seem evident that they’ve recalled things from previous days.

Although it doesn’t relate to goldfish alone, modern science shows us that fish are much cleverer than people once believed. They have complex social structures, the ability to learn and some species can even use tools.

Where Did the Myth Come From?

It’s not clear exactly where the myth that goldfish memory is only 3 seconds came from or why it’s so widely perpetuated. However, it’s likely it was designed to make people feel better about keeping them in small bowls with little to occupy them.

If you know that goldfish are intelligent, thinking creatures, then keeping them in a tiny tank with no form of mental stimulation is cruel. But, if you believe they have a memory span of three seconds, it doesn’t seem like a big deal, because they don’t even remember what happened four seconds ago.

So, what should you do with the knowledge they can remember things for months? Get them a decently-sized tank with a range of ornaments and hidey holes, and perhaps some live plants to root around in.

Goldfish Memory: What Are the Facts?

We know for sure that goldfish don’t have three second memories, but how? As well as observation and common sense, a range of scientific studies support it.

Researchers at Plymouth University in the UK taught goldfish to request food by pushing a lever. They then changed things up by only releasing food when the first pressed the lever at certain times of day.

Amazingly, these fish not only knew that pushing the lever would get them food, but successfully recalled what times of day they’d receive the food in exchange for pressing the lever, showing that goldfish can not only remember things, but they have a good sense of time, too.

Scientists at an Israeli university taught fish to associate a piece of classical music with food. Five months after the end of an initial one month training period, they still came swimming over, looking for food, when they heard that piece of music being played.

Although it might not stand up to rigorous scientific standards, Jamie Hyneman, on the Discovery show Mythbusters, trained goldfish to swim through a simple maze, indicating that these fish could both learn and remember—no three second goldfish memory here.

These are just a handful of the studies and experiments that show they can remember for far longer than 3 seconds. Although there’s no definitive answer to exactly how long they can retain information, it’s likely to be at least four or five months, if not indefinitely.

These studies retested the fish after a set amount of time to see if they could still remember but didn’t keep testing to see when they forgot. It’s entirely possible that goldfish can retain important information for years. Possibly even for their whole lives.

So, What Does This Mean for Goldfish?

As we touched on above, the fact that goldfish have longer memories than many people believe means that keeping them in unstimulating environments is cruel. You should provide them with as large a tank as you can, and certainly never keep them in a bowl.

Not only are bowls too small, but they also distort the way the world looks outside the bowl for your fish.

Based on the fact goldfish may well remember things for years and are probably more intelligent than you give them credit for, try to provide them with a stimulating home environment. Give them plants or caves to hide in and explore, a suitable substrate to forage in, and change up the layout of their tank now and again, to keep things interesting.

It’s also true that goldfish are social creatures, so we’d recommend keeping at least two together—just make sure you get them a large enough tank. If kept alone, they can exhibit signs of depression, and in some countries, it’s even illegal to keep a single goldfish, due to animal welfare laws.

Video: Do Goldfish Really Have a 3 Second Memory?

The following video examines the myth of the three second memory. Watch to learn more about some of the experiments done that disprove this myth, as well as other interesting facts about goldfish intelligence.



Goldfish don’t have a 3-second memory, and it’s likely they can remember things for months.

Knowing this should change how we treat our fish, making sure they have an interesting and stimulating environment to live in. They do not swim around continually amazed at new areas of their tank every 3 seconds. They remember these things, and can very likely get bored.

But also, we should know that they can recognize us, and remember how we treat them. Be kind to your fish, and they will remember this and enjoy seeing you, perhaps coming to the surface to feed from your hand if it’s what you regularly try to do.

Mistreat them, they will remember this also, and your enjoyment of your fish will be far from as good as it can be.

Happy fish keeping!

Wendy Kathryn

Hi, I'm Wendy, the owner and creator of this website, an experienced fish keeper and avid student of the art since 2010. My aim is to help beginners avoid the many possible mistakes when getting started in this wonderful hobby.