Bubble Eye Goldfish: Fish Species Profile

Characteristics, Origin, and Helpful Information for Hobbyists

Bubble Eye Goldfish

Getty Images/LucaLorenzelli

Is that goldfish holding his breath underwater? Although it may look like that, the bubble eye goldfish has been bred to have very large sacs of fluid under their eyes. This benign fluid pocket predisposes these fish to eye trauma, so careful consideration to aquarium setup, décor, and tank mates must be given to these fish.

Species Overview

Common name: Bubble Eye Goldfish

Scientific name: Carassius auratus

Adult size: 6 inches

Life Expectancy: 6 to 15 years


Given the bubble eye goldfish's delicate eye structures, there is a fair amount of concern for their welfare and wellbeing within the aquarium community. Please carefully consider if these fish are a good fit for your tank and fish lifestyle. The bubble eye goldfish are slow swimming fish that cannot easily see in front of them and are prone to injuring their delicate eye tissues. They should not be housed with fish that are aggressive or that might nip at their bubble eyes.


Family  Cyprinidae 
Origin  Asia 
Social  Peaceful 
Tank Level  Top, mid-dweller 
Minimum Tank Size  20 gallons 
Diet  Omnivore 
Breeding  Egg layer 
Care  Easy 
pH  6.0 to 9.0 
Hardness  6 to 12 dGH 
Temperature   55 to 80F (10 to 27 C)

Origin and Distribution

Descending from the original genetic line of Comet goldfish, the bubble eye goldfish has been manipulated over countless generations to have this eye deformity as well as a double tail fin. Selective breeding has produced this fancy goldfish variety and others, such as Ranchus, Orandas, and fantails. These fish are never found in the wild unless they have been released by aquarists.

Colors and Markings

Like all other goldfish, the bubble eye goldfish can be orange to yellow to white. If they have been bred with a Shubunkin goldfish, they may have a calico pattern. They will often have hunched bodies and a downturned tail peduncle.

As their name denotes, these fish have a large sphere of fluid under each of their eyes. Contained within a delicate flap of skin, these protrusions may hinder your fish's ability to swim and forage. You will see these bulges wrinkle and bend with the movement of your fish, which is normal for this variety of goldfish.


When it comes to tankmates for the bubble eye goldfish, you should take careful consideration of other fishes' swimming and eating ability. The bubble eye goldfish is a very slow, awkward swimmer and requires patience for eating. When you have two giant pillows under your eyes, eating can be a difficult process. If possible, the bubble eye goldfish should only be kept with other bubble eyes or telescope goldfish varieties, such as black moors. These fish with visual deficits will all have equal opportunities for eating without much competition.

Even invertebrates, such as shrimp, may pick at your Bubble Eye Goldfish's sensitive eye tissue, not making them a suitable tankmate. Snails are perfectly safe from predation from these fish but will often quickly overwhelm a tank with their prolific breeding.

Bubble Eye Goldfish Habitat and Care

When it comes to habitat and care of the bubble eye goldfish, this variety requires more care and consideration. Given their large orbital structures, their habitat should be relatively free of décor, especially any abrasive leaves or other sharp decorative items. Your bubble eye should be able to easily navigate all areas of his or her tank and not have any caves or crevices they might get stuck in.

Given the likelihood that your fish will at some point cause a self-inflicted injury, maintaining good water quality is paramount. Good water quality is key to providing your fish with a healthy response to any disease or injury. Be sure to test your water chemistry regularly and stick to a regular maintenance routine.

Although foraging in the substrate of a tank is a normal goldfish behavior, it can easily damage your bubble eye goldfish's delicate eye tissues. No or minimal substrate is recommended to avoid injuries.

Another consideration when setting up an aquarium for your bubble eye is water flow. With their short, often hunched bodies and eye impediments, these fish can be easily pushed around by the outflow from your aquarium filtration. You may need to limit your filtration, which means your tank should have lots of extra volume, or baffle your outflow with a sponge or other device that spreads out filter return over a larger surface. Pay attention to how your bubble eye goldfish swims around their tank and take note of any areas they cannot linger in for long without getting pushed away.

If you notice a tear in one of your bubble eye goldfish's delicate eye skin folds, do not attempt to repair it on your own. If the tear is less than 1 cm long, there is a good chance it will heal on its own, provided you maintain good water quality and your fish is eating a well-balanced diet. If the tear is longer, you may want to consult with your aquatic veterinarian. It is very difficult to suture these tears closed, due to the delicate eye tissue, and using glue can cause a very painful inflammatory reaction in fish. Your aquatic veterinarian will best guide you in ensuring your fish does not suffer any secondary infection from a potential non-healing wound.

Bubble Eye Goldfish Diet and Feeding

When it comes to feeding your bubble eye, you must be patient. Given that this variety of goldfish has both visual and swimming difficulties, it takes them considerably more time to eat than most other fish. This is why we recommend they are only kept with other slower, fancy goldfish or only with other bubble eyes.

When choosing a food, you may want to go with a slightly higher protein (33-38 percent) than a regular, maintenance goldfish diet. Fancy varieties have to expend more energy to swim normally, so some extra calories can help them be more active.

Although not commonly recommended for fancy goldfish, the bubble eye goldfish should be fed a floating diet. Normal goldfish foraging behavior, rooting around in the substrate, can cause eye issues. Feed your fish slowly and allow them to eat one pellet at a time. If they are unable to find their food, it will cause additional waste for you and your filter to clean up.

Gender Differences

Like most goldfish, the bubble eye males may display breeding tubercules on their operculum, or gill cover, and on the front edges of their pectoral fins. However, sometimes fancy goldfish do not show these external characteristics. If your fish is struggling to swim and eat, they may not be interested in developing robust reproductive structures, which is normal for most goldfish varieties.

Breeding the Bubble Eye Goldfish

If you are interested in breeding your bubble eye goldfish, please consider carefully the welfare of these fish. You may consider using a veterinarian to perform a full exam, including an ultrasound to confirm sex, to ensure the fish you want to breed are in good health.

Like breeding other goldfish, the bubble eye like to have plant roots on which to lay their eggs. Be sure to chose soft plants, preferably live, such as Anacharis, to ensure your fish are not injured in their spawning glee. After laying their eggs and fertilizing them, move the mom and dad to another tank so they do not eat their eggs or offspring. After a few days, fry will hatch and require a high protein and fat diet for normal development. There are commercial fry foods available, or you can grow infusoria to feed the fry.

Breeding goldfish can result in a variety of traits. Do not assume that two bubble eye goldfish will only produce bubble eye offspring. You will often get other traits from the fishes' lineages.

More Pet Fish Species and Further Research

If you're interested in the Bubble Eye Goldfish, you may want to check out these other goldfish varieties:

Check out additional fish breed profiles for more information on other freshwater fish.