A goldfish with giant BUBBLES on its face?
Meet the Bubble Eye!
It’s one of those fish that you either love or hate.
But one thing is for sure:
This fish is very unusual.
Today we’re going to cover everything you’ve ever wanted to know about this exotic breed!
Quick Facts about Bubble Eye Goldfish
Species Name: | Carassius auratus auratus |
Temperature: | 75Β°-80Β° F |
Lifespan: | 30-40 years |
Size: | 5-6 inches on average |
Hardiness: | Not very hardy |

Image Credit: Jonathan Leung, Flickr
Bubble Eye Goldfish Overview
The Bubble Eye is a fancy goldfish, with most falling under the category of dorsalless breeds. Higher quality ones have a smooth back with no odd spikes or lumps. However, the Chinese have developed a variety that does have a dorsal fin and a much longer tail (phoenix tail). These aren’t often seen in the Americas.
As one of the more rare varieties, they definitely aren’t as easy to find as the Fantail or Black Moor at your local pet store. They come in all colors, from self-colored (solid) black, white, red, yellow, to red and white or even the harder to find Sarasa, red and black or calico patterns. The black ones remain coveted. Bubble eyes are one of the more petite fish, only reaching around 5 inches in length when fully grown. This breed is definitely one of the most delicate of all the others. Pond life is out of the question.
Some people go as far as to think that they are too delicate to keep any other fish at all with, in case they bump into each other, so they must live in permanent isolation…
Bologna! They aren’t made of tissue paper. But they don’t do well with sharp objects.
Don’t Pop Your Bubble!
But the most unusual feature of the Bubble Eye is beyond a doubt what it was named after…
It’s bubbles!
Those two huge sacks of fluid that bulge out from beneath its upward-gazing stare. After the fish reaches about 6-9 months old, they start to develop. And they continue to grow larger until the fish reaches about 2 years old when the skin of the sacks becomes thinner.
This is crazy!Β A Bubble Eye’s bubbles can actually explode if damaged (often by an oversized filter).

Image Credit: Mikhail Esteves, Flickr
YIKES! Good thing for this fish that a sack can grow back if popped, but it probably won’t be as big as the other one.
On a more scientific note: Researchers have discovered the fluid inside these sacks stimulates the growth of human cells. (I do not by any means advocate what they are doing.)
Bonus: Some goldfish even have bubble sacks on their chins – giving them 4 total! This is considered more of an unintentional mutation. Other breeds of goldfish occasionally develop a bubble on their chin too, but they don’t seem to be as prone to it.
Questions of Ethics: Should Bubble Eyes be Banned?
It’s probably one of the most heavily hybridized goldfish. Ever.
The highly unusual appearance of this fish has raised some serious questions in the minds of some: “Is this animal cruelty to breed fish that look so weird?”
I think a lot of people picture them to be miserably laying at the bottom of the tank all the time, unable to move much. But watch them in action and you’ll learn how spunky they really are. π
Their activity level doesn’t seem to be any lower than other goldfish breeds. Many owners attest that they are used to their eye protrusions and don’t believe they experience any discomfort from them as they swim normally.

Image Credit: Lawrencekhoo, Wikimedia Commons
Granted:
There are some Bubble Eyes – usually older ones – with eye sacks so large that they have difficulty swimming and it does seem to impair their quality of life.
All goldfish… even single-tailed goldfish… have been selectively bred to some extent. I personally think they are not over-bred. Take good care of them and they will live just as long as the other breeds. But I understand where others are coming from who see it differently.
How to Properly Take Care of Your Bubble Eye
Bubbles eyes are prone to injury and eye infection. An infected eye sack may become cloudy or discolored. This can lead to blindness if it progresses too far, which is why prevention is very important.
The first step? Proper care. Because they are more fragile, they are not recommended as a beginner fish.
What is the Best Tank Size?
Make sure the tank has no sharp objects that could pop the sacks and that the filter is not too strong, which could suck up the sack as the fish swims by (yikes!). Even artificial plants can be pokey, so try to go for silk plants or live ones without pointy protrusions. But be sure that the fish has enough room to grow to its full potential! That’s why each one needs 10 – 20 gallons of space to itself.
A bowl is probably the worst home you could put your fish in, so please don’t do that. Why? For starters, they don’t allow the fish to get enough oxygen because of the small surface area. And they also get dirty so fast that they make your fish get sick π

Image Credit: Lerdsuwa, Wikimedia Commons
What is the Best Temperature for your Fish?
Bubble Eyes prefer a range between 70-80 degrees F. This ensures that their immune systems are not stressed by too much cold, but not overheated either. They are sensitive to the temperature being too cold, so you may want to have a heater for the water.
Are Oranda Goldfish Good Tank Mates?
Let’s be clear about something: You should only keep goldfish with other goldfish, no other kinds of fish. Not even algae eaters (especially not algae eaters)! They aren’t a good mix at all and can end up stressing and even hurting your goldfish.
Because Bubble Eyes are not the strongest of swimmers…
… It’s a good idea not to keep them with the more competitive breeds of goldfish like the slim-bodied fish or fancies like the Ryukin or Fantail.
Instead, other Bubble Eyes make the best companions. But clumsier Pearlscales and Ranchus might also work well for friends.
And There’s More…

Image Credit: lienyuan lee, Wikimedia Commons
Weβve only scratched the surface when it comes to caring for your Bubble Eye goldfish. There just isnβt enough time to go into all the detail! But don’t worry β I wrote a complete care guide called βThe Truth About Goldfish.β
It contains ALL the information you will ever need to make sure your fish doesnβt just survive, but THRIVES. Iβm sure you want yours to reach its full potential, right? You can take a peek at it here.
What to Feed Your Bubble Eye Goldfish
Proper feeding plays a very important role in goldfish health. It’s very important to make sure they are able to do what they love to do best:
Forage! Make sure there are always lots of fresh veggies in the tank. Veggies also provide the fiber that keeps their digestive tract functioning properly. In addition, they will need a high-quality staple diet. Live foods are always a great, healthy treat too π
You can learn more about goldfish food in our feeding article.
Breeding Bubble Eye Goldfish
Breeding Bubble Eyes can be a challenge due to their eyes getting in the way.
But they can still lay over 1,000 eggs at a time!
Males will show breeding stars on their fins and gill plates during breeding season.
A period of cold weather followed by warmer water can help get them to spawn.
Wrapping it All Up
I hope you’ve enjoyed learning about this amazing fish. So, what do you think? Is the Bubble Eye YOUR favorite, or maybe you happen to own one? Feel free to leave your comment below. I’d love hearing from you π
Featured Image: Arunee Rodloy, Shutterstock
I have 2 bubble eyes im a 20 gallon tank (I’m in the process of getting a bigger tank) but the smaller one, Nemo, popped one of her bubbles and it is just a flap of open tissue, it looks painful. I dont have anything sharp in the tank and have never seen any aggressive behavior from either of them, so what should I do and how did this happen? Thanks!
Keep the water very clean. It could even get stuck in gravel if there is any.
No… But now I got another bubble eye to add with my other 2.. And the other 2, (pee wee and fatty), they are happy and constantly foraging. My new fish, Delyla, isnt eating and looks depressed just sitting in the corner… She isn’t eating, and the twice I saw her eat she spit back out after chewing. She also had a clear string of poop. What should I do? I don’t want to stress her out more by moving her, but I don’t want her to get pee wee and fatty sick. I did a 50% water change
If she isn’t eating, it’s a good idea not to feed. If she is new and sick, I would isolate her from the others to help protect them.
So I have one bubble goldfish named Chuck and I have 1 platy and 1 molly with 2 very small Cory catfish in a 15 gallon tank they don’t seem to be agressive to my bubble goldfish but do you think I should separate my platy, molly, and Cory catfish? I was thinking about getting another bubble goldfish but idk if I should put him in the 15 gallon tank
Yes I do. I really think bubble eyes should not be kept with such fish. 15 gallons is only enough room for one goldfish.
My kids also brought a bubble eye goldfish home and its having its own tank. But lately it seems the fluid sacks became to big and heavy. Its laying on the bottom on its fluit sacks most of the time and ita having a bloodish patch on each sack.its swimming with utmost difficulty to feed. Its breaking my heart. What can I do? (The fish is even called after me).
Sounds like an eye infection π A good place to start would be heavy water changes.
Is a bubble eye goldfish pretty active or will it swim. Around for alittle and sit in one spot then swim around some more
That sounds pretty normal to me. It should spend more time swimming than sitting though.
Themba NCOMANZI
Waipukurau. Hawke’s Bay – NEW ZEALAND
Just got 2 bubble gold fish for my 3 yr old son. Looking forward to their happy relationship (my boy and his fish).
Bubble eyes are a lot of fun π I bet your boy will love them.
We bought 2 bubble eyes, one white and one silver, a few months ago. The silver one has quadrupled in size, the white one has barely grown at all. Is this normal?
One may be getting more food than the other, causing it to grow faster. Maybe try hand-feeding π
Would you think a African dwarf frog would be fine with a bubble eye fish beacuse I have been thinking about getting a bubble eye goldfish but I have a frog named Kermit and I donβt want to get rid of him
You could try, but if the bubble eye gets big enough the frog could become lunch π
Would two be good for a 20 gallon tank or 1
1 is better, 2 is doable but a bit tricky. π
Squishy (bubble eyed goldfish) has just been sitting alot, I’ve checked the water, changed the water.. I feed him/her tropical flakes because that’s what the store fed him/her before I bought it.. could that affect squishy? Oh and how can i tell Male or female…
What exactly are you water test results for ammonia, nitrite, nitrate and pH? How long has the tank been set up? Please see this article for telling if the fish is male or female.
IS IT OKAY TO HAVE ONE IN A TANK WITH 4 OTHER LITTLE FISH? OR DO THEY NEED THEIR OWN TANK.
Depends on the size of the tank, Kate π
My bubbled eye named Oscar, a fish nipped itβs bubbles as I was not aware that they went meant to be together, so itβs bubble is popped, I am so sad and depressed, I have watched them again and there is no vicious Behaviour now, I thank no they were just play so 1, should I get rid of my fish, 2 how long will it take for oscars eye to be back to Normal, or start to heal. Thanks
Yes get rid of the fish. It will never grow back fully to the other size but given a few months you should see some growth.
Hello! I hace a 20 gallon aquarium a had a bubble eyes before and the are lovely. My problem is the always got theyre eyes sacks stuck in the filter. When I could do something about it, it was too late. I have a cascade aqua clean 20 that is not that strong. Still got stuck. Poor guys. Can you recomend a type of filter or filtration device that could Jeep my tank clean and not harm the goldfish bubble eyes? Thank you for the care guide and all.
Thank you for your kind words, Ivan. For bubble eyes sponges are the way to go. You can either use a sponge filter or put a large sponge on the filter or pump intake. This will protect them.
Ok pretty clever ! Thank you ill try it and let you know!
I have a bubble eye who popped its sac on my filter. My bubble eye shares a tank with my black moor. I’m afraid for the health of my black moor. Will the fluid in the sac kill him?
A large water change would be in order.
I had a bubble eye for 3 years and it died last night. One of its sacks was cloudy. Was there something I should have treated it with?
It could have been an infection, those delicate sacks are prone to problems. Not all treatment is successful though so don’t beat yourself up.
My Bubble eye died and I get another, which also died 5 days later. Got them in my 187 litre with Black Moor, Black Oranda (large sized, about 5 inches) and Black Ranchu. Those 3 is very active and healthy (my small black ranchu even injured by my canister filter because I forgot to put the strainer but he is now healing well), but I doesn’t seem can keep bubble eye.
I always see him hiding behind the submerged filter before meeting his demise today. Did Oranda attack him? Or because my canister filter is too powerful (1400/L per hour for 187 L) and stress him out?
But I know, no more Bubble Eye again.
I’ve had the same thing happen to me with other breeds of goldfish. But bubble eyes are definitely more delicate. Sometimes if they are small, young, weak or recently transported it’s just too much. π
When will your book be in stock? And this is a great website! thanks!
Hoping next month π And thanks!
Hi, love the site!
I have a 1 year old bubble goldfish who’s having some issues and I can’t find information anywhere! One day his sacs where filled with white liquid with no other signs of illness over a month they now have returned to clear but looks like he has white pebbles in his sacs. They move around and are kinda gross but apart from this he is healthy. Is this normal or something anyone knows about?
Thanks in advanced
Normal, after a bubble infection.
Thankyou so much I’ve been so worried!
Is it ok to keep a small bubble eyed goldfish with a albino pleco if itβs a 29 gallon tank?
I would think you shouldn’t have water quality issues, but I’d be concerned about aggression from the pleco with a bubble eye myself.
My daughter is wanting to get a Bubble Eye. What find of filter do we need to get? I read that the filter can suck up their bubbles and pop them. Also since they are so sensitive, what kind, if any, decorations can be added to the tank? TIA
I’d use a sponge filter. Live plants for decor.