May 25

Sarah Robertson

Telescope Goldfish – How to Maintain The Most Distinctive Goldfish Breed

Goldfish are a common choice for anyone looking to get into the hobby of keeping fish. They are a hardy and attractive breed that comes in a wide variety of colors and shapes. One of the most popular types of goldfish is the Telescope goldfish.

The telescope goldfish is named for its distinctive feature- two large, protruding eyes that give it the appearance of staring at the world through a telescope. This physical trait is the result of a genetic mutation and is what sets this breed apart from other goldfish.

Unlike other goldfish varieties, these fish species are not said to be fit for beginners. In this article, we will see why this is the case and what you need to know about keeping telescope goldfish as pets.

Telescope Goldfish

What is Telescope Goldfish?

The first thing to understand when caring for a telescope goldfish is what exactly these fish are. The telescope goldfish is a variety of fancy goldfish, having a rounded or egg-shaped body with large protruding eyes that are set on the end of long cone-like stalks.

These stalks are mounted on the sides of the fish’s head. The stalks can reach 3/4 of an inch in length in certain situations. The eyes in juvenile fish under six months old appear normal sized and the telescope effect does not begin to fully manifest until the fish reaches maturity.

Telescope Goldfish Origin 

The Telescope Goldfish were initially created in China in the early 1700s as the Dragon Eye Goldfish or Dragonfish. They were renamed Demekin in Japan during that period and are still known by that name today.

Telescope Goldfish Appearance

The Telescope Goldfish is a rounded, egg-shaped fancy goldfish with telescoping eyes and a smaller size than the Fantail Goldfish. The only difference between it and the Fantail Goldfish is in the telescoping eyes and reduced length of the tail fin. The body is tiny and stubby, with a huge head and a split caudal fin. The dorsal fin is single and the pelvic fins are on either side of the anal fin.


The Telescope Goldfish is a beautiful fancy goldfish that comes in a variety of hues, including glistening metallic and nacreous scale types. However, the majority of them are matte. The following are the different color types of Telescope Goldfish available:

  • Red
  • Calico

  • Chocolate

  • Blue

  • White

  • Black called as Black Moor goldfish

  • Red and White

  • Black and White

  • Bi-color

  • Tri-color

  • Chocolate with orange pom-poms

Telescope Goldfish Size 

The average size of a Telescope Goldfish is 5 inches (12.7 cm), although they have been observed to grow considerably larger in certain aquariums. They can reach up to 8 inches (20.32 cm) when maintained in ideal conditions.

Ideal conditions include a spacious tank with plenty of hiding places, a varied diet, and regular water changes.

Telescope Goldfish Lifespan

Telescope Goldfish Lifespan

The average lifespan of a Telescope Goldfish is 10-15 years, although they have been known to live for much longer in certain cases.

Telescope Goldfish Behavior

The Telescope Goldfish is a very peaceful fish that does not show any aggression towards other tank mates. They are generally shy and reclusive by nature and prefer to stay hidden among the plants and decorations in their tank.

Because of their telescopic eye, they are considered visually handicapped as they cannot see things directly in front of them. This means that they are prone to get bullied by more active and bolder tank mates, making it important to find a compatible species of fish when choosing tank mates for your Telescope Goldfish.

They cannot readily compete for food with other types of goldfish and should be given pellets or flakes that sink to the bottom of the tank so they can eat them easily. This is the reason why these fishes are considered not fit for beginners.

Telescope Goldfish Care

Telescope Goldfish are not suitable for novices to keep. Because of their extremely telescopic eyes, they can't clearly see things that are in front of them. As a result, they need highly specialized care that may only be given by someone with considerable fishkeeping expertise. However, if you are up for the challenge, here are some tips on how to take care of your telescope goldfish:

Telescope Goldfish Tank Setup

Setting up a Telescope Goldfish tank is not as difficult as it may seem. However, because they are such delicate creatures, it is important to take your time and do it right the first time. You will have to consider the size of your tank and how many fish you want to stock, as well as which accessories you will be adding.

Aquarium Size

A Telescope Goldfish requires at least a ten-gallon tank. It's ideal to start with a 20 - 30 gallon tank for your first goldfish and then add 10 gallons for each additional fish as necessary. A high proportion of water per fish will dilute the amount of waste and reduce the frequency of water changes.

Water Temperature

The optimum water temperature for goldfish in an aquarium is about 65-72 degrees Fahrenheit. The pH level should be between 6.0 and 8.0, and the water hardness should be between 5 and 19 dGH. Goldfish can also live in slightly brackish water if the salinity is kept below 10%, even though they usually prefer freshwater habitats.


Telescope goldfish need a strong filtration system as they are known to create a lot of waste. To keep the water clean and fresh, you must also do a 30% weekly water change. All fancy goldfish enjoy a quiet still environment, regardless of type. If the current is too strong, the fish will have a hard time finding food and will become stressed.

There are many different types of filters available on the market, but any type of mechanical aquarium filter will do. It is best to include biological media in the filter such as ceramic rings or bio-balls for maximum filtration.

Tank Decor

You may include a variety of plants in your aquarium. Live plants, in addition to looking lovely, are also believed to oxygenate the water and remove undesirable nitrates. However, it’s best not to use floating plant species in a goldfish aquarium.

Telescopes require a large swimming area in the aquarium. These fish are poor swimmers who would be unable to deal with too much obstruction or dense planting. Plants should be positioned toward the back of the aquarium, and any overgrowth must be trimmed away to keep the fish from getting tangled.

You may also add a gravel substrate to your aquarium. Goldfish prefer a sandy bottom, but any type of gravel will do. The amount of gravel you'll need depends on the size of your tank and how deep you want the substrate to be. A good rule of thumb is 1-2 pounds of gravel per gallon of water.

Anything with sharp edges or rough surfaces that may harm your fish's protruding eyes or trailing finnage should be avoided when selecting aquarium decor.

Tank Maintenance

To keep your Telescope Goldfish happy and healthy, you will need to perform regular maintenance on their tank. This includes:

Regular water changes - ideally 20% per week or 50% every two weeks.

Adding fresh aquarium salt (1 teaspoon per 5 gallons of water) at a rate of no more than 1 tablespoon per day.

Add appropriate aquarium additives as needed. This can include medications for parasites, bacterial infections, fungal infections, and fin rot.

Telescope Goldfish Tank Mates

Because of the species' poor eyesight, big eyes goldfish might not be able to compete for food with their faster tank mates, causing them to fail to thrive. Telescope eye goldfish will also have a hard time competing for food with quicker, more agile tank mates.

Carassius auratus should be kept with other goldfish, such as the black moor, lion head goldfish, celestial goldfish, and bubble eye goldfish. Species that are confirmed fin nippers, such as tiger barbs, should not be kept with Telescope goldfish.

Telescope Goldfish Feeding


Telescopes are omnivorous, like all goldfish species. That means they consume a variety of plant and meaty foods, just as other goldfish do. You may observe that the goldfish munch on some types of algae if you have algae in your tank. Certain plants are also edible, and the fish will nibble on them. Vitamins, minerals, proteins, fats, and fibre are all essential to a good diet. A deficiency of any one of these nutrients can harm your fish's health.

  • Goldfish Pellets and flakes- These are the most common type of goldfish food, and there are many brands available on the market. It is best to choose a high-quality food that contains all the essential nutrients your fish need to stay healthy.
  • Live or frozen foods - You may also feed your goldfish with live and frozen foods such as brine shrimp, bloodworms, daphnia, and tubifex. However, it is best to avoid feeding these foods routinely because they contain a lot of fat which can result in digestive problems for your pet.

  • Vegetables and fruits - Goldfish enjoy vegetables such as peas, lettuce, and spinach. You may also give them some fresh fruits like apple, melon, broccoli leaves, and squash (but not the skin of these vegetables or fruits as they are not easily digestible).

Tips To Feed 

  • You should only feed your goldfish as much food as they can consume in 2-3 minutes.
  • Feed less during winter as the fish are less active and have a slower metabolism.
  • A varied diet is a key to keeping your goldfish healthy, so be sure to mix up their meals.
  • Remove any uneaten food from the tank to prevent it from decomposing and polluting the water. Frequent water change is also recommended.
  • Do not feed foods such as bread, potato chips, and cheese as they will not be properly digested and can pollute the water.

Telescope Goldfish Diseases

Even though goldfish are hardy fish, they are still susceptible to a number of diseases. Some of the most common diseases that affect Telescope goldfish include:

  • Tailor Fin Rot: If your fish's fin tips start deteriorating and the tissue disintegrates, tail or fin rot might be setting in. This is caused by poor water quality and/or an improper diet.
  • Dropsy: The scales on an affected fish's body will start sticking out, and the abdomen will appear bloated. This is caused by a bacterial infection and is often fatal.
  • Ich: Also known as white spot disease, ich appears as small white spots on the fish's body. It is caused by a parasitic infection and can be deadly if left untreated.
  • Swim Bladder Disease: This is caused by a build-up of air in the swim bladder, which leads to the fish floating near the surface. It can be caused by overfeeding the goldfish or by eating too big food particles.
  • Fungal Infections: Fungus may appear on your Telescope Goldfish's body, particularly if the tank water is dirty or if the fish suffers from an injury. You can treat this disease with medications and by improving water quality.


If you think your Telescope Goldfish is sick, it is best to follow these steps:

  • First, check the water quality. Ammonia, nitrites, and nitrates should all be at zero. The pH should be between 7.0 and 8.0.
  • If the water quality is good, then observe your fish's behavior. Are they eating? Swimming normally? Hiding a lot?
  • If you think your fish is sick, quarantine them in a separate tank. This will prevent the disease from spreading to other fish.
  • Take a water sample to your local fish store or vet for testing. They will be able to tell you what disease your fish has and how to treat it.
  • Treatment depends on the disease. However, some of the most common treatments include adding aquarium salt to the water or using medications such as antibiotics and anti-fungal medicines.


Preventing disease is always easier than treating it. To keep your Telescope Goldfish healthy, follow these tips:

  • Maintain good water quality by doing regular water changes and using a filter.
  • Quarantine new fish before adding them to your tank.
  • Don't overfeed your fish.
  • Avoid overcrowding the tank.
  • Remove any sick fish from the tank immediately.
  • Add aquarium salt and medications (as needed).
Telescope Goldfish Breeding

Telescope Goldfish Breeding

The majority of Goldfish are bred in groups as small as five individuals. They can be reproduced in groups of up to five fish, although they are sociable animals that will most likely breed in larger gatherings. Goldfish will only hatch in the wild when spring arrives. To reproduce them in an aquarium, you must replicate natural circumstances.

  • Selecting a Breeding Group
    A common misconception is that Telescope Goldfish are unable to breed in captivity. This is untrue. In fact, they are quite easy to breed, as long as you have a good group of fish to choose from.
    When selecting a group of fish to breed, look for healthy individuals with no signs of disease. The fish should also have a good body shape and be of similar size.
    The fish must also be of the same age, as this will improve their chances of successful breeding. Ideally, you should select a group of 5-8 young fish that are between 2-3 years old. This will give you the best chance of success.
  • Conditioning the Fish
    Once you have selected a group of fish, you will need to condition them for breeding. This involves making sure they are healthy and well-fed.
    The first step is to quarantine the fish. This will help to prevent any diseases from spreading.
    Next, you will need to provide the fish with a high-quality diet. This can be achieved by feeding them live foods, such as brine shrimp or bloodworms. You should also add some vegetable matter to their diets, such as algae wafers or blanched lettuce.
    Finally, you will need to raise the temperature of the water. This will simulate the changing of seasons in spring, which is when Goldfish typically spawn.
    After 2-3 weeks, your fish should be fully conditioned and ready to breed.
  • Tank Set-up
    Once the fish are conditioned, you will need to set up a breeding tank. The tank should be at least 20 gallons in size. It should also have a good filter and plenty of hiding places.
    To simulate spring conditions, you will need to raise the temperature of the water. The ideal temperature for breeding Goldfish is 75-80 degrees Fahrenheit.
    You should also add some live aquatic plants to the tank. These will provide the fry with places to hide and will help to keep the water tank clean.
  • Spawning
    When the fish are ready to spawn, they will become very active. The males will chase the females around and nudge them with their snouts. Eventually, the female will release her eggs and the male will release his sperm.
    Once the eggs have been fertilized, you will need to remove the parents. This is because they may eat the fry. If you don't have another tank to move them to, you can simply scoop them out with a net.
  • Telescope Goldfish Fry Care
    The eggs should hatch within 3-7 days. The fry will begin feeding on their yolk sac immediately, so you do not need to worry about feeding them at this stage.
    Once they reach 2-3 weeks in age, you can feed them good quality flake food. You can also add live foods to their diets, such as brine shrimp or bloodworms.
    As the fry grows, you will need to remove them from the breeding tank and put them into a grow-out tank.
    You should continue to feed them a high-quality diet and provide them with plenty of hiding places. The fry should be ready to sell or trade when they reach 4-6 months in age.


How Big Do Telescope Goldfish Get

The average size of a Telescope Goldfish is 5 inches (12.7 cm), although they have been documented to grow considerably larger in certain aquariums. However, when maintained in ideal circumstances, they may reach up to 8 inches (20.32 cm).

Where Do Telescope Goldfish Live

Where Do Telescope Goldfish Live 

In captivity, they can survive in both outdoor ponds and indoor aquariums. However, they are typically considered to be cold-water fish and prefer temperatures of around 65-75 degrees Fahrenheit (21-24 degrees Celsius). They also require plenty of space to swim in, so it is important to provide them with large tanks or outdoor ponds. If they do not have enough room to move around freely, they may become stressed and become more susceptible to illness.

Are Goldfish Telescopes Aggressive?

They are very peaceful fish and are not known to be aggressive towards other species. It is very important not to put them together with other aggressive or predatory species, as this could lead to injury or even death.

Do Telescope Goldfish Need a Heater?

No, these are coldwater fish and do not require a heater in their tank. In fact, they prefer waters that are on the cooler side, around 65-72 degrees Fahrenheit (18-22 degrees Celsius). If the water is too hot, they may become stressed and more susceptible to illness.

What Is Panda Telescope Goldfish?

The black and white variety of the telescope goldfish is commonly known as the panda telescope goldfish. This unusual coloration gives these fish a distinctive appearance that sets them apart from other varieties. The panda variation is especially popular among fish enthusiasts and hobbyists.

What Is Black Moor Goldfish?

Black Moor Goldfish is basically a black version of the Telescope Goldfish. It is characterized by a dark metallic coloration and large, protruding eyes that give it the appearance of having "black goggles." However, its eyes don't protrude quite as far as those of the Telescope Goldfish.

What Are Orange Pompoms? 

It is the rarest and most sought-after color variation of the Telescope Goldfish. The orange pompom variety is characterized by a deep vibrant orange coloration, along with large orange pom-poms or growths on its head. These goldfish are much prized by hobbyists and are in high demand among fish enthusiasts and breeders alike.

What Size Tank Does a Telescope Goldfish Need?

The minimum requirement for a Telescope Goldfish is 10 gallons. For your first goldfish, start with a 20 - 30 gallon tank and gradually increase the size of the tank by 10 gallons for each additional fish.

Can Telescope Goldfish Live Alone?

Yes, Telescope Goldfish can be kept alone or in groups. However, it is important to remember that all goldfish are social animals and should not be kept in small tanks, so it is best to keep them in groups of 3 or more.

Final Thoughts

The Telescope Goldfish is a fantastic addition to any aquarium or pond. They are docile, beautiful, and do not get too big. However, these fish are considered unsuitable for novices because of their protruding eye, which makes it harder for them to find food. This is a variety of goldfish that requires extra care.

Aside from their prominent eye, caring for them is comparable to caring for any other goldfish. A tank of at least 10 gallons is required, the water temperature should be kept around 65-72 degrees Fahrenheit, and plenty of space to swim should be provided. Feeding high-quality food is also important for their health, as they are prone to getting obesity and other health problems.

Even though they may seem a bit more challenging to care for, Telescope Goldfish is definitely worth the effort and make excellent pets. If you are thinking of adding one to your aquarium or pond, be sure to do plenty of research beforehand so that you can provide them with the best possible care.

Sarah Robertson

I am a passionate blogger who also happens to be a fish keeping enthusiast. Writing about my hobby is something that I absolutely love to do, and it's no secret that my chosen topic is always centered around fish keeping.

Sarah Robertson

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