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Bubble Eye Goldfish Care: All You Need to Know

Bubble Eye Goldfish Care: All You Need to Know

The bubble eye goldfish are as strange as they come. It is arguably one of the most exotic fish breeds in this planet. It originates from China and its unique features are as a result of mutations in the course of breeding through its various generations.

They are mainly ornamental fish and therefore are reared as pets. Just as its name suggests, this fish has got bubbles which are fluid sacs underneath its eyes.

This guide takes an in-depth look into the bubble eye goldfish. You will get to understand its origin, physical characteristics, and its lifespan.

What’s more, you will learn is its care needs including the type of feeding, tank size and set up, tank mates compatibility, breading and more.

About Bubble Eye Goldfish

Bubble eye is a delicate fish that comes from the Goldfish heritage. What people love and hate about the bubble eye is its unique features.

It has a smooth curved back because it does not have a dorsal fin giving it an egg-shaped body structure. It also has a double tail.

Though there exist scanty details about its origin, it is believed to belong to the carp goldfish heritage that was farmed in ornamental ponds in China as early as the 1900s. It is certainly a product of selective breeding of a variety of goldfish breeds.

Does bubble eye goldfish have bubbles?

Their most outstanding feature is the large fluid-filled sacs that develop just below their eyes. These fluid sacs slightly upturn their eyes, but not nearly as dramatically as those of the celestial eye goldfish.

The Bubble Eye goldfish looks pretty much like any other goldfish when it is small. However, at the age of 6 to 9 months, bubbles start to grow which reach their full size at the age of two.

These fluid sacs slow down the fish as they increasingly grow heavy. Moreover, because the eyes are turned upwards, they have poor vision. When you add the fact that this breed does not have a dorsal fin, its movements are bound to be slow and wobbly.

Can bubble eye goldfish pop?

Typically, the sacs are of the same size and color. These bubbles are fragile especially when they reach their full size. The sacs generally do not rapture on their own. However, sharps objects or even contact with other fish can cause the sacs to rupture.

When this happens, the fish can get sick or even die. The great news is that, more often than not, these sacs can grow back but not to their full size.

What color are They?

They come in a variety of colors, including orange, red, blue, calico, and black. Others are bi-colored; either red and black or red and white. There is also a rare species that has a bright yellow color.

How big is a Fully Grown Adult?

A fully grown bubble eye goldfish is usually about 5 to 6 inches long making them one of the smallest variety of the goldfish. However, some grow beyond this size even up to 8 inches long especially when reared in optimal conditions

What Is Their Life Span?

Their average lifespan is about 10 to 15 years but can live even longer when properly cared for. However, the bubble eye goldfish is considered one of the most challenging varieties of goldfish to take care of.

This is especially due to their delicate nature and unique anatomy. As such, a great number of this breed die prematurely because their owners do not take time to learn how to properly take care of them.

Carassius auratus

Bubble Eye Goldfish Care

Thanks to their unique care needs, they are only suitable pets for experienced aquarists. Forget about the typical goldfish care approach.

The bubble eye needs keen attention which mainly entails providing a safe environment for them to thrive. This is because they are susceptible to injury and eye infection which can result in blindness or even death in the worst case scenario.

What should I feed them?

They have a similar dietary requirement to that of the rest of the goldfish. They are omnivorous by nature thus they thrive on a varied diet which can include plants and animal foods.

Good nutrition helps them develop a healthy bone structure, strong immune system, good color and also attain optimal health.

Allow them to forage, because this is their best feeding method. Ensure that you always place enough fresh veggies in the tank so that they can forage throughout the day. The dietary fiber from the vegetables helps to keep their digestive tract at its tip top function.

Live foods are also a great, healthy option. The goal is to achieve a balanced supply of protein, carbohydrates, and fat. Good quality flake or pellet foods specifically designed for the fancy goldfish is a good source of all the nutrients the bubble eye needs in a single daily feeding ration.

You can as well occasionally supplement the pellet food with fresh or frozen foods such as shelled peas, mosquito larvae or bloodworms to keep their diet more interesting.

Careful not to overfeed them though because they don’t have stomachs. When overfed or fed incorrectly, they are likely to suffer from various digestive problems. Avoid feeding them a single large meal, and settle for three or four small meals throughout the day.

The Aquarium Set-up

The best way to keep the bubble eye safe and healthy is to have an appropriate aquarium setup.

What is the best tank size and shape?

Bigger is always better in this case. A fishbowl might be a tempting idea, but it is really a bad idea. For starters, the small surface area does not allow the fish to get enough oxygen. Moreover, due to their high levels of waste production, the water gets dirty pretty fast which can make your fish sick.

If you are planning to keep a single bubble eye, you need a tank that can hold at least 20 to 30 gallons. For each addition of fish in the tank, add an extra 10 gallons of water.

The best approach to picking the right tank size is to establish beforehand the number of fish you would like to keep in the long run. This will help you choose a tank that is large enough to house this future number.

The shape of the tank also plays a critical role in contributing to the health of the bubble eye. A rectangular tank that is wider than tall is recommended. This is because it optimizes the water surface area to ensure proper supply of oxygen.

Do they have a preferred water temperature?

The bubble eye goldfish thrives in water temperatures that fall within the range of 65 to 80 degrees Fahrenheit. Too much cold stresses their immune system, while too much heat is not good for them either.

It is recommended to have a water heater to maintain these ambient temperatures because indoor temperatures usually drop below 60 Fahrenheit at night or during the colder months.

Test the waters

One of the leading killers of aquarium fish is poor water quality. The water might not look cloudy or muddy, but could be extremely toxic for your fish.

Checking for water toxicity should start before you add the fish into the tank in the first place. Tap water often contains chloramines and chlorine which can poison your fish.

These toxins can be easily eliminated by a water conditioner. It also neutralizes ammonia and nitrite which are the other major toxic elements found in new aquariums.

Once the fish has been added to the tank it is recommended to use test kits regularly to test for toxicity levels in the water. These include ammonia, nitrate, nitrite, KH, pH, and GH levels to ensure that they are within the recommended ranges.

Do I need to install a filter?

Filters are a must item in any goldfish aquarium. The bubble eye is such a feeder and subsequently produces a lot of waste which can become poisonous if not removed.

The capacity of a filter is measured by the amount of water it can cycle per hour. This is referred to as the flow rate. It is recommended to use a filter that has a flow rate of between 5 to 10 times the volume water in the fish tank.

As such, if you have a 30-gallon tank, you should look for a filter that has a flow rate of 200 to 400 gallons. Given that the bubble eye is not a good swimmer, a very strong current may make its living conditions pretty uncomfortable.

Their delicate sacs may also get sucked in by the filter inlet and possibly get damaged. To avoid this, ensure that you have baffled the filter inlet with a mesh or netting.

Bubble Eye Goldfish

Change water regularly

How we wish that bubble eye goldfish care would be a one-time, “set-it-and-forget-it” affair. This is far from the truth because it will require more than placing your fish to your tank and then feeding it regularly. Just like cats need their litter boxes changed so does the bubble eye needs their water changed regularly.

Though the filter facilitates proper circulation throughout the tank, this does not cut the chase in terms of keeping the water clean. Filters generally convert the harmful substances in the water, to a cleaner substance (nitrate).

Eventually though, the nitrate can buildup to harmful levels. Thus, the best solution to maintain clean water is to change is regularly using an aquarium siphon.

The goal is to maintain the nitrate levels in the tank below 30. It is also recommended to keep an eye on your fish. Fortunately, watching your goldfish is such an enjoyable pastime. In case you notice changes in behavior or appearance, change the water.

Do they need a substrate?

Substrate not only decorates your aquarium, but also influences the chemistry of the water and hence the well-being of the fish. The Bubble Eye is generally a poor swimmer. You are more likely to find it resting on the aquarium bed.

The gravel used in a Bubble Eye aquarium should be smooth. Jagged edge plants and objects are likely to rupture the fluid sacs increasing the risk of infection or even death.

The substrate should also be made up of large particles that cannot be swallowed by the fish. Fine gravel like sand is will be swallowed by the fish which often results in digestive problems or even death.

Suitable tank mates

You need to carefully select the bubble eye tank mates due to their sensitive nature. Their poor vision and slower movements make it hard for them to compete for food with the more agile goldfish.

The aggressive types can also rupture their sacs. They should only share a tank with other slow-moving goldfish such as the Black Moors, Celestials or the Lionhead.

This way, each breed will have a fair chance of access to food and won’t get hurt or stressed by the more agile fish.


We have previously mentioned that the fluid-filled sacs under the eyes give the bubble eye goldfish poor vision. The males have a challenge finding the female while the female has a greater challenge to find the spawning medium.

To facilitate breeding, add more males than females in a single tank. Cluttering the breeding tank aggravates their poor vision making their movement and breeding much harder.

People have a problem distinguishing the male and female when naturally breeding them. Females have a slender body structure than their male counterparts and thus are often mistaken to be male.

During the breeding season, some white tubercles appear on the male’s gill plates and the pectoral fins. This is the best indicator of gender. You can as well give hand spawning a try.

Some extra tips

When handling the bubble eye goldfish, it is important to protect them from injury. This is especially when transferring them from one tank to another, or adding them to a new tank for the first time.

First, you need to acclimate the fish to the new environment by floating the bag on the new tank for about 20 minutes to match the water temperature.

Ensure that you gently place the fluid sacs on your hand, as you take the fish out of the water. With this comprehensive bubble eye goldfish care guide, you are bound to have a satisfactory fish keeping experience!