Goldfish Facts – Top 10 Goldfish Facts

Goldfish facts

We love fascinating goldfish facts here at The Goldfish Tank – and there really are some weird and wonderful facts about goldfish!

Check out our top 10 goldfish facts below and then – if ten facts isn’t enough for you! – learn even more goldfish facts here!

Goldfish Fact #1: Goldfish don’t have stomachs!

Goldfish don’t have stomachs and should therefore be fed easily digestible food in lots of small feeding sessions, rather than lots of food at once. This is also why goldfish produce so much waste and why you need a filter to keep their water clean. Read more…

Goldfish Fact #2: Goldfish have been known to live for over 40 years!

With the proper care, goldfish can live for decades. This goldfish was said to be 45 years old. Read more…

Goldfish Fact #3: The collective noun for goldfish is “a troubling”

Just like you’d say “a herd of cows”, you’d say “a troubling of goldfish”!

Goldfish Fact #4: Goldfish can recognise people’s faces

Goldfish can tell different faces apart and are able to distinguish between different shapes, colors and sounds.

Goldfish Fact #5: Goldfish have a memory-span of at least three months

Many people say that goldfish have a memory of just a few seconds, but this is a myth! Goldfish have a memory span of at least three months! Read more…

Goldfish Fact #6: Goldfish can grow to over a foot long

Goldfish can be stunted by being kept in tanks that are too small for them and where the water quality is poor. This means that they don’t reach their full potential size. However, goldfish can grow to be over a foot long when kept in the right environment. Check out this massive goldfish!

Help I have a goldfish bowl cover

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Goldfish Fact #7: Selective breeding has led to a huge variety of goldfish shapes and colours

Humans have bred many different varieties of goldfish. Read more…

Goldfish Fact #8: Goldfish can’t close their eyes!

Goldfish have no eyelids, so they have to sleep with their eyes open!

Goldfish Fact #9: Goldfish have been kept as pets for over 2000 years

Keeping pet goldfish dates all the way back to ancient China! Read more…

Goldfish Fact #10: Goldfish can see more colors than humans can!

Goldfish don’t like to be kept in the dark and, unlike humans, they are able to see ultra-violet and infra-red light.

Want more? View more goldfish facts here!

Alternatively, why not learn some more about goldfish care?

Chat with other goldfish lovers in our FREE forum! Visit now and learn more about your goldfish!
  • Carson cambre

    Can gold fish poop?

    • TheGoldfishTank

      Yes, goldfish definitely poop. They poop A LOT!

      That’s why you need to make sure you have a big tank for your goldfish and don’t feed them too much. If your tank is too small or you give them too much food then the water will get polluted and will be very bad for your fish.

      • michelle

        I think that’s what happened to my goldfish and it died :(

  • michelle

    Do fish sleep and when they die do just float then just float to the bottom ?

    • TheGoldfishTank

      Hi Michelle,

      Goldfish don’t sleep like we do, it’s more like “resting”. We have an article on it here.

      When they die, goldfish will sometimes float to the top and sometimes stay at the bottom of the tank. Usually, they will sink at first, but float to the top later (though you should always remove dead fish from your tank as quickly as possible).


  • Jaime

    if you feed your goldfish to much will it explode?

    • TheGoldfishTank

      They won’t explode, but they will have trouble pooping (you may see a trail of poop dragging behind an overfed goldfish!) and may struggle to swim properly. That’s why it’s so important to feed your goldfish properly.

  • Jaime

    when my goldfish died, it got a white patch on its nose. It kept floating to the top and I would poke him back down. After this he died. What was wrong with my poor fishy? He was 3 years old. :(

    • TheGoldfishTank

      Hi Jaime,

      Sorry to hear about your fish!

      It’s really difficult to say what the white patch was without seeing it. It could have been an injury – goldfish like to stick their noses into gravel and around objects, so if there’s anything sharp in your tank then they can easily hurt themselves – and if the water quality isn’t great (high ammonia levels) the injury won’t heal properly. Plus, high ammonia levels can damage fish’s gills too.

      If it was more of a white spot, like salt or sugar, and there was more than one spot, then it could have been something called “ich” or “white spot disease“.


  • Gabby

    I recently purchased my own goldfish, but have become worried the tank is too small? What is the right size tank?

    • TheGoldfishTank

      Hi Gabby,

      We recommend 20 gallons for a fancy goldfish and 30 gallons for comet/common goldfish. You can read our post on goldfish tank sizes here.

      You can sometimes get away with smaller tanks than this for a little while, but you should quickly upgrade to a tank of at least this size if you want your fish to live a long life and grow to its full potential.


  • Mikey

    Ive recently Just given my Veil Tail too a friend as she out grew my tank. However i’m looking to get new fish to restock the tank.
    I don’t want another Veil Tail (no matter how pretty they are) as they do poop alot and were alot of work. What fish do you recommend for a coldwater tank that don’t poop as much and are quite hardy and easy to look after?

    • TheGoldfishTank

      Hi Mikey,

      All goldfish poop a lot, so if you’re looking for a hardy fish that doesn’t poop very much then we’d probably look for something other than goldfish.

      Have you considered guppies? You can read more about them on our sister site (though it’s a brand new site, so there aren’t that many posts live yet!) and there’s loads of information and advice online. They’re hardy and you could keep a really nice looking, colorful group of them.

      It may also be worth looking into platies, mollies, corydoras catfish and neon tetras.


  • Anonymous

    I recently won a goldfish at a fair and it is living in a bowl they were also selling, I put special crystals in the tap water to get rid of any chlorine and change the water daily. How long is the fish likely to live? It’s a bit cruel that they’re given away as prizes, am I better off finding a pond and letting poor old Ken this fish live his life in the wild!?

    • TheGoldfishTank

      Hi there!

      You’re right, it is cruel that some fairs still give goldfish away as prizes – they’re kept in small bags for a long time, normally given away without any advice about how to care for them, and as you say, small bowls that aren’t actually suitable for them to live in are often sold at the same time.

      With daily water changes, your fish will probably live several weeks or possibly a few months. It’s unusual (though not unheard of) for goldfish kept in bowls to live longer than that. You may start to notice its gills moving rapidly (as if it is “breathing” heavily), redness developing around its gills and your fish rubbing itself up against the walls of the tank. These are all signs that poor water conditions are irritating it.

      However, you should *not* release it into the wild. Doing so would probably be illegal (depending on the laws in your country) and potentially damaging to the ecosystem.

      If you’re interested in keeping goldfish, whether this one lives or not, then the best thing to do would be to buy a suitable tank (and the necessary equipment, such as a filter) for it.

      If you don’t really want to keep goldfish and you’re just concerned for this one fish that you happened to win then, realistically, it’s not worth you buying all the equipment you need. If possible, find a friend with a suitable tank or pond and give the fish to them.

      If neither of those options work for you then the best you can do is keep it in the largest container you have, continue to treat the water and continue to do daily water changes.

      Hope that helps! Do let us know how you get on.


  • bianca

    I really want a goldfish, I’ve had other species of fish before and they have lived for about two years. This will be my first goldfish and I’ve been reading up on your facts on how to take care of a goldfish.

    I have a huge bowl ready for the new goldfish but I realized that you said to buy a tank instead, what if you have a huge bowl. Is it still alright and also do we have to buy a filter or can we clean the fish bowl daily?

    hope that you can help me!1

    • TheGoldfishTank

      Hi Bianca,

      Thanks for your comment!

      Do you know how big the bowl is? Either in gallons or liters or in inches high and across? While it may seem “huge” compared to other goldfish bowls, most of those bowls are very, very small. So your bowl probably isn’t really that big compared to a goldfish tank and the space goldfish actually need.

      Goldfish definitely need a filter.

      It’s not really a case of “cleaning” your tank, but rather building up a colony of bacteria in the filter sponges. If you’ve not already then check out our article on cycling your tank.

      Unless it really is a very, very big bowl, you’ll probably struggle to cycle it properly and achieve stable water conditions, due to the relatively small volume of water.

      We’d strongly recommend a properly cycled tank for goldfish. And you definitely need a filter. Maybe consider other types of fish for the bowl and wait until you have a bigger tank before getting goldfish?

      Let us know how you get on!


  • Kobie Seeton

    I was given two Comet fish in a small bowl (takes +- 4 liters water.. I am stressing now after reading about them.You also say it is a good idea to give them fresh water daily (I mean some fresh) How long will they last? The fish I mean. Thank you

    • TheGoldfishTank

      Hi Kobie,

      Thanks for your comment.

      Unfortunately that is way, way too small a bowl even for one fish, nevermind two. The best thing you could do (if you think you might want to stick with keeping goldfish whether these particular fish survive long or not) would be to buy a big tank and a proper filter.

      That way, you give the fish you have the best chance of surviving, but also have a tank ready for your next goldfish in case these ones don’t live very long.

      If you don’t want to get a big tank (or can’t for any reason) then do daily water changes and only feed them a very small amount to keep the water as clean as possible (don’t worry – goldfish really don’t need very much food!).

      You asked how long they’ll last… In a bowl that size; probably a matter of weeks or a couple of months at most. Goldfish have been known to live a long time, even in very small bowls, but most don’t last very long without a big tank and a filter unfortunately.

      Good luck! Let us know how you get on!


  • juliana

    I’m writing from Portugal. I’ve had goldfish at home since I was a kid and I believe I take good care of them: they usually live up to 8 years, more or less. I think one of my current goldfish is dying – he can barely swim, lays on the floor of the tank most of the time, floats a little… He’s been like this for 2 days… Is he really dying and why is it so slow? Is he suffering? I’m sorry to be asking these questions, but my previous goldfish didn’t take this long to die, I’m worried.

    • TheGoldfishTank

      Hi Juliana,

      It’s really difficult to know what’s wrong with your goldfish without seeing him but we’ll try to help!

      Is your tank overcrowded at all? Is it properly cycled? How often do you feed your fish? Do any other fish in the tank appear to be ill?

      If he’s been overfed then he could be bloated and have problems with his swim bladder. You could try not feeding for a few days and then feed only a very small amount (preferably a pea or two, boiled and crushed into small pieces).



    outside pool with 3 goldfish. 1 large 2 smaller ones been in together for 6months.The large one is now chasing the smaller ones can you tell me why, perhaps mating? Can anyone tell me why please, should I catch one and put in a bucket for a couple of hours

  • Pingback: Pet Care Tips: 5 Interesting Facts About Fishes |()

  • TheGoldfishTank

    That sounds really interesting Zack!

    To be honest, we’ve never tried anything like this so we’re not sure why some fish would be quicker learners than others. Possibly the bigger fish are older and have better developed brains and therefore better memories?

    Do keep us updated on how you get on with your project. Do you have a video of your fish going through the maze? It would be great to post it here for people to see!


  • john mcbride

    Is a 39 litre orb ok for 2 gold fish

  • Kylee

    Hello . I went and bought 6 gold fish from Wal-mart . I placed them inside the tank while inside the bag i bought them in , to get them use to the water i had placed in the tank . The next day i wake up , and one of them is floating by itself and looks as it is dead ; but i do not know if it is . The other 5 fish will not go around it , they are all staying on the other side of the tank . IS IT DEAD ? *and its only been a day*

  • carlyraejepson2006

    me and my gold fish had a stearing contest 😛 it went on forever!!! now i know why ..

  • TheGoldfishTank

    Unfortunately, that tank is too small even for one goldfish. We recommend a minimum of 20 gallons for one fancy goldfish, and then an extra 10 gallons for each additional fish.

    And comets/commons need even more space!

    • Troller Pod

      Well its to late now one died already.
      How much water do you need for one SMALL AKA (1-1.5in) common goldfish.
      And if I were to add a snail would i need more water?
      THANKS :)

      • TheGoldfishTank

        We actually recommend 30 gallons for one common goldfish.

        You could probably get away with 20 gallons for a while if you had to, but you’d need to upgrade eventually.

        Although that may seem like a lot for a 1-1.5 inch fish, you need to base the tank size on how big the fish will grow, not how big it is currently.

        • Troller Pod

          So will he die if I don’t upgrade soon?
          (last question sorry)

  • james

    my fish are named panda cause i have a panda platy and comet, chaos, and skillex cause they fight together. my platy is in a little tank separated from my goldfish.

    • mohadeseh

      hi im mohadeseh i have 2 goldfish and their name is Googooli and Magooli
      i dont know but when i see them….they move their body….
      what do they want?

  • Rocky

    Hey, I have a common or comet goldfish (I’m really not sure which he is) and I’ve had him for a year and a half after winning him at a carnival. He’s in a 60 gallon tank right now, and my dad wants to get some more fish. We were thinking about getting some bristlenose plecos (maybe 2?) because they won’t eat his slime. My dad is also interested in getting another goldfish, but I’m not sure if that would be a good idea. If that would be okay, how many more goldfish could we add?

  • Sandy

    Hi How do you tell if a goldfish is male or female ????????

  • KittyKat

    Um…gee, an 11 inch goldfish in a 10-gallon tank. Yikes. I would suggest either getting him a bigger tank or moving him to an outdoor pond. IIf that doesn’t work, try getting him a friend or two. But make sure they’re around the same size, or else the 11 inch goldfish will eat the smaller ones.

  • Cheryl Metcalfe

    Hello, I have a 120 gal. pond with 12 different goldfish, a couple fantails. a few calicoes, and inexpensive feeders. Over the past year, this is the 2nd time the same fantail has had her tail fins shredded, I have never observed any other fish acting aggressive toward her. It seems to happen over night. Please help me if you can.

  • Donna Halliday

    i live in north carolina and have a 3 gallon tank with a fancy goldfish…i named him fred…and a algea eater…i am going to be moving 530 miles away…9 hours…how can i transport them and not lose em…its not like having my dogs…this is a different thing for me