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The Comet Goldfish Is The Fish You Need To Start Raising Now

Ready to add a colorful new species to your freshwater fish tank? If so, you should consider the Comet Goldfish.

This fish has captured the hearts of beginner and experienced fishkeeping hobbyists since the late 1800s, and for good reason. This fish is absolutely gorgeous, with a long forked tail and vibrant coloration. Although there are several variations of the Comet Goldfish, this species is easy to care for and a fun, playful fish to keep in any community tank.

Consider these tips for raising a Comet Goldfish, and you’ll be getting along swimmingly in no time.

Comet Goldfish

Comet Goldfish Background

Comet Goldfish 1

Also known by its scientific name of Carassius auratus auratus, the Comet Goldfish was originally created in 1800s through a process of selective breeding that was done on wild carps in Prussia. These fish are one of the most popular in the fishkeeping hobby, offering a hardiness to most water conditions as well as a gorgeous appearance.

Comet Goldfish Appearance And Behavior

Comet Goldfish 4
Photo by WabbyTwaxx

Thee fish can live for up to fourteen years in captivity, growing well over eleven inches in length. While they are naturally orange, they are now available in multiple colors and patterns due to their selective breeding.

Comet Goldfish are named for their long golden tails, which flow outwards as they swim through the water and look not unlike a comet. This is the main difference between Comet Goldfish and common goldfish. While the latter species has stiff, immovable fins, Comet Goldfish have fins that are long and flowing. However, their bodies tend to be much smaller than those of common goldfish.

Comet Goldfish also differ from common goldfish in that they have heavily forked tails and slim bodies. They have a single anal fin and characteristic tail fin. They have normal, non-bulging eyes, as well as scales that are flat instead of bumpy.

They come in a wide variety of colors, with yellow-orange and orange-red combinations the most common varieties. However, you can also find Comet Goldfish being sold in colors such as black, yellow, white, brown, and red and white. There is also a Comet Goldfish that has a cloud-like color and pattern  – this is known as the Shubunkin goldfish.

Comet Goldfish are popular because they are extremely active. In fact, they are one of the most active breeds of goldfish and as a result are extremely enjoyable to watch. Fast, active swimmers, they spend most of their days exploring and interacting with their surroundings.

These fish are incredibly smart, possessing the unique ability to recognize their owners as well as their tank surroundings and decorations. You might consider switching up their tank design or decorations every few months, which will help keep their surroundings new to them and prevent any possible boredom.

Comet Goldfish are not usually aggressive toward other species or members of their own species, but they can be aggressive during feeding. You can reduce this behavior by feeding at both ends of the tank. This will reduce nearby competition for food and eliminate the likelihood of aggressive behavior.

Comet Goldfish Tank And Water Requirements

Comet Goldfish 2

Because Comet Goldfish are descendants of wild carp, their habitat should match the natural environment of these fish. Wild carp, also referred to as Prussian carp, were native to Asia and resided in slow-moving bodies of water, such as calm rivers. They were also found in lakes, ditches, and large ponds, most of which were low in water level.

In your aquarium, try to replicate this environment to the greatest extent possible. If you plan on keeping more than four fish, you will need to own a pond in which to house your fish. Fish kept in smaller quantities can get by with a large, rectangular tank that is longer than it is wide. This will give them plenty of extra space in which to swim.

You can lay down fine, small gravel as a substrate, as well as anything else that is light and will not scratch their delicate scales.

All Comet Goldfish prefer colder waters, meaning you need to keep your tank an appropriate distance away from any potential heat sources. A cool room is better than a warm room for Comet Goldfish, something you will need to keep in mind during periods of warmer weather, as well as if you have your tank located near a heat source. Water that is too hot can kill your goldfish or cause lifelong damage to their nervous system.

The water should be kept at temperatures between 50 and 75 degrees Fahrenheit. This means that most tanks will not need supplemental heating, and you can instead keep the tank at an adequate temperature through the radiant heat of the room.

The ideal pH for Comet Goldfish will be between 6.5 and 7.5. You can’t provide too much filtration in a Comet Goldfish tank, as they produce a shockingly high amount of bioload and waste. This can very quickly impact the condition of the water, so investing in a good filter is crucial. You can incorporate an inexpensive hang-on-back filter or a canister filter to accomplish this.

Many people (including pet shop workers) believe that goldfish only grow to the size of the tank. This is not true. Comet Goldfish can row quite large, so you will need at least 50 gallons of water per Comet Goldfish. Ideally, a 75 gallon tank would be even better.

Decorating A Comet Goldfish Tank

Comet Goldfish 3
Photo by Ray

You must include plenty of live plants in your Comet Goldfish tank. Comet Goldfish like plants to nibble on, as they will occasionally serve as food, and they also serve to oxygenate the water. Plants provide shelter so that your Comet Goldfish feel safe and at home as well. You might consider options like Java fern, hornwort, and anacharis as good choices.

All goldfish, but Comet Goldfish in particular, like decorations. These decorations provide your Comet Goldfish with a source of entertainment. They like to have lots of places to explore, being active swimmers and curious fish by nature. They will learn how the decorations work and will play and chase each other around the decorations if you have more than one. Make sure you add a few types of decorations but avoid adding too many so that they won’t feel overcrowded. A good rule of thumb is to have one quarter of your tank decorated to every three quarters of open water.

Consider rearranging your decorations every time you change the tank water. This will prevent your goldfish from becoming bored, and will also reduce the likelihood of algae build up, as you will likely clean your decorations when you move or remove them.

What Do Comet Goldfish Eat?

Comet Goldfish 6
Photo by Andrea Bailey

As descendants of Prussian carp, Comet Goldfish require a varied, wholesome diet. In the wild, carp are omnivores, eating both plant and animal foods. They will eat plants, small insects, algae, and anything else they can find. Most of their diet will consist of vegetation, which offers fiber as well as plenty of nutrients to keep them healthy and thriving.

The best way to feed your Comet Goldfish is by giving them pellets or flakes. These flakes will include all of the nutrients your Comet Goldfish needs and will provide most of their dietary requirements. However, you should keep in mind that flakes shouldn’t be the only source of food for your goldfish, as you will want to provide other foods to keep their diet varied and interesting. Remember, goldfish adapt and get bored easily!

For this reason, you might want to think about adding meat sources like small insects, mosquito larvae, bloodworms, and worms. You can feed vegetables like algae, cucumber, mashed peas, carrots, zucchini, lettuce, and broccoli. You can even add fruit like fresh or frozen blackberries, blueberries, and strawberries.

It can be a challenge to feed your Comet Goldfish the appropriate amounts of food. Many beginning goldfish keepers are unaware of proper feeding amounts. You should try to feed them Comet Goldfish twice or three times a day, only feeding them as much as they can eat in about two minutes.

Afterwards, remove any remaining food. A common issue among Comet Goldfish is bloat, which is the result of overfeeding and is easily avoidable. Comet Goldfish can also develop digestive problems if the water is kept too cold, so try to keep the waters above 50 degrees Fahrenheit at all times.

Comet Goldfish Tank Mates

Comet Goldfish 5
Photo by WabbyTwaxx

Comet Goldfish are not suitable companions for most species of freshwater fish. While they are not aggressive, they have very specific housing and feeding requirements that can make it challenging, if not impossible, to keep them with other species.

This is because Comet Goldfish tend to live in freshwater, but not tropical freshwaters. The warm water temperatures preferred by most popular freshwater fish will be way too hot for your Comet Goldfish. They also have a tendency to consume lots of food, meaning it is easy for your other fish to become malnourished.

That being said, the best tankmates for Comet Goldfish will be other Comet Goldfish, as well as other koi and goldfish species. The best species will be those that are the same size as the Comet Goldfish  – think species like the Common Goldfish, Shubunkin, Jikin, and Wakin goldfish varieties.

Other potential tankmates include Rosy Barbs, Weather Loaches, Zebra Danios, and Bristlenose Plecos. However, you will need to be very careful with the temperature and set-up of your tank. The temperature will need to be at the very top of the range of what is comfortable for your Comet Goldfish and at the very bottom of what is best for these other species.

When in doubt, consider just keeping Comet Goldfish with other Comet Goldfish. You can keep multiple Comet Goldfish together in a single tank, but you will need a very large tank. Remember, you need 50 gallons for every Comet Goldfish, so just four Comet Goldfish will require a massive 200-gallon tank.

Common Comet Goldfish Diseases

Comet Goldfish are prone to some of the most common diseases among other aquarium species, including fungal infections, swim bladder disease, fin rot, and goldfish ich. Most health problems can be prevented by providing good, clean water and conducting regular water changes. Maintaining adequate temperature and pH can also help keep disease away.

Ich is one of the most common diseases in goldfish. Also known as white spot disease, this usually affects new goldfish that are stressed. Ich is caused by parasites and makes it look like your goldfish is covered with small grains of salt. He or she may start breathing heavily and scratching themselves against tank objects. You will need to treat the affected goldfish and/or aquarium tank with a salt and heat method for at least three days. Eliminating stress can help prevent this disease.

Swim bladder disease is another common ailment. This causes your goldfish to sink to the bottom of the tank or to experience difficulties swimming. Make sure the water is clean, as unhealthy water is one of the main causes of this disease. You may also need to feed lower-protein foods or change out the other types of foods you are feeding your fish. Consider feeding vegetables and daphnia to your goldfish, and keep an eye on the pH and ammonia levels in your tank.

Fin rot is also common among Comet Goldfish. Fin rot is a bacterial infection that can occur on its own or as a secondary infection from stress or injury. This appears as ragged or red-streaked fins. The torn fins eventually become white as bacteria eat away at them. It can completely deteriorate the fins, and since goldfish cannot regrow their fins, this is definitely a detrimental condition you will want to avoid. Make sure you have excellent water quality and treat with salt if you notice fin rot has started to set in.

It is pretty easy to determine whether your Comet Goldfish are feeling under the weather. Signs of illness include strange behaviors like rubbing against objects in the tank or lying listlessly at the bottom. You might also notice cotton-like growths or discolored patches on the scales and fins. Goldfish can easily fall victim to bacterial infections, fungal diseases, and parasites, particularly if you aren’t taking care of them appropriately.

Breeding And Life Spans Of Comet Goldfish

Comet Goldfish can be incredibly difficult to breed, particularly if they are being kept in an aquarium. It is much easier to breed these fish in a pond, but keep in mind that if you are keeping multiple varieties of Comet Goldfish in a pond, they can crossbreed and create different varieties.

To initiate spawning behavior, you need to provide a trigger. The easiest way to trigger breeding is to slowly raise the temperature of the pond. Keep them in cooler water, ideally around 58 degrees Fahrenheit, for about a month. Then, gradually increase the water temperature until it reaches 70 degrees Fahrenheit. This will mimic the natural warming of the water that occurs during the spring months in the wild.

You will begin to notice signs of whether this has been successful almost immediately. Males will begin to chase females around the pond, attempting to touch their stomachs. If he is successful, she will deposit her eggs into the plants of your pond or tank. Generally, she will release about 1000 eggs at a time.

You should use a spawning mop inside your tank or pond. This way, you can remove the eggs after they have been laid. You can put the eggs into an aquarium to prevent the parents from eating them after they have been laid.

Allow the eggs to remain in the aquarium for about a week, keeping temperatures high at around 70 degrees Fahrenheit. They should hatch in about seven days, and will swim within just a few days. Then, you will have a whole group of new Comet Goldfish fry for you to raise or sell.

Comet Goldfish will grow quickly, stretching by about fifty percent each week. They will reach full size in about three or four years, with most growing up to a foot in length when they are fully grown. Comet Goldfish can live between four and fourteen ears, with the range in lifespan accounting for the various common diseases that can limit their growth.

Is A Comet Goldfish For You?

As long as you have plenty of space for them to swim and plan ahead for their rapid growth, Comet Goldfish are a suitable choice for any fishkeeper. These fish add an active, fun-loving personality to your tank, and are incredibly intelligent and enjoyable to keep. Brightly colored and possessing vivacious personalities, these fish are not overly challenging to keep.

Although they can grow incredibly large and therefore require appropriate accommodations, Comet Goldfish are not challenging fish species to raise. They are a great addition to your household pond or aquarium, and should be at the top of your list when you are considering which species you would like to raise.

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