Comet Goldfish

Comet-tail Goldfish, Sarasa Comet, Pond Comet

Family: Cyprinidae Comet Goldfish, Sarasa Comet, Comet-tail GoldfishCarassius auratus auratusPhoto © Animal-World: Courtesy David Brough
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Fun, active, clean, hearty, colorful cheap fish.  brady

Comet Goldfish look just like regular goldfish but with a much longer, deeper forked tail fin!

The Comet Goldfish is also called the Comet-tail Goldfish or Pond Comet.This fish was the first variety of the single-tail goldfish to be developed with a long caudal (tail) fin. It was developed in the United States from the Common Goldfish in the early 19th century, presumably by Hugo Mullert of Philadelphia who then introduced them in quantity into the market.

Being a further development of the Common Goldfish, the Comet is very similar to it. This sometimes causes confusion, especially since both these fish have an almost identical body shape. However the fins on the Comet Goldfish are much longer, especially the caudal (tail) fin. Its caudal fin is also more deeply forked. On both these fish the caudal fin is held fully erect.

Comet Goldfish
Comet Goldfish

The adult size of the Comet Goldfish is smaller too. Yet even though they are a bit smaller goldfish than the Common Goldfish, they are every bit as durable and can be kept in either an aquarium or in an outdoor pond. Both are inexpensive and readily available.

The Comet is generally a more reddish orange in color while the Common Goldfish is more orangish. Their primarily color is the reddish orange, but they are also available in yellow, orange, white, and red. They can also be found as a bi-color red/white combination and occasionally they are available with nacreous (pearly) scales, giving them a variegated color.

Common Goldfish
Common Goldfish

Other types of Comet include the Sarasa Comet. This variety has long flowing fins and is characterized by a red-and-white coloration that holds a resemblance to a koi color pattern called 'Kohaku'. The Tancho Single-tail Comet is a silver colored variety with a red patch on its head.

One of the hardiest of the gold fish varieties, the Comet Goldfish are recommended for beginners. They are an easy fish to keep as they are not picky and will readily eat what is offered.

These fish can be quite personable and are delightful to watch. They are some of the most graceful of the elongated goldfish, emphasized by their long tail. They are active, rapid swimmers and tend to leap out of the water occasionally, so having a lid on an aquarium is good idea. They are also very social and thrive well in a community.

Along with the other elongated goldfish, such as the Common Goldfish and the Shubunkin Goldfish, the Comet varieties make good pond fish. They are hardy and can tolerate cold water temperatures. They are moderate in size but are active and fast, so will get along well with Koi. Also Comets usually won't uproot plants, but they will readily spawn so can quickly overpopulate your pond.

For more goldfish information, see:
Goldfish Care: Fancy Goldfish and Goldfish Diseases


Geographic Distribution
Carassius auratus auratus
Data provided by FishBase.org
  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Cypriniformes
  • Family: Cyprinidae
  • Genus: Carassius
  • Species: auratus auratus
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Comet Goldfish - Quick Aquarium Care
  • Size of fish - inches: 4.0 inches (10.16 cm)
  • Minimum Tank Size: 15 gal (57 L)
  • Temperament: Peaceful
  • Aquarium Hardiness: Very Hardy
  • Temperature: 65.0 to 72.0° F (18.3 to 22.2° C)
  • Aquarist Experience Level: Beginner
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Habitat: Distribution / Background

The goldfish of today are descendants of a wild carp fish, known as the Prussian Carp, Silver Prussian carp, or Gibel Carp Carassius gibelio (syn: Carassius auratus gibelio) which was described by Bloch in 1782. For many years it was believed that goldfish had originated from the Crucian Carp or Golden Carp Carassius auratus auratus described by Linnaeus in 1758, but more recent research is pointing toward the former.

These wild carp originated in Asia; Central Asia (siberia). They inhabit the slow moving and stagnant waters of rivers, lakes, ponds, and ditches feeding on plants, detritus, small crustaceans, and insects.

Goldfish were originally developed in China, but by the 1500's goldfish were traded to Japan, to Europe in the 1600's, and to America by the 1800's. The majority of the fancy goldfish were being developed by Oriental breeders. The results of this centuries long endeavor is the wonderful goldfish colors and forms we see today. Today domesticated goldfish are distributed world-wide.

The Comet Goldfish was the first variety of the single-tail goldfish to be developed with a long caudal (tail) fin. It was developed in the United States from the Common Goldfish in the early 19th century, presumably by Hugo Mullert of Philadelphia who then introduced them in quantity into the market. It is one of the more than 125 captive bred varieties of goldfish that have been developed.

  • Scientific Name: Carassius auratus auratus
  • Social Grouping: Groups
  • IUCN Red List: NE - Not Evaluated or not listed - There are no wild populations of this captive bred variety.

Description

The Comet Goldfish is an elongated, flat-bodied variety of goldfish. The head is wide but short and it has a smoothly tapering body shape, from its back and belly to the base of its caudal fin (tail fin). The caudal fin is long, deeply forked and generally stands fully erect. Comets have a natural life span of up to 14 years, though possibly longer if kept in optimal conditions.

The Comet Goldfish is a bit smaller than the Common Goldfish, but even so, the environment it is kept in is a determining factor on whether your pet grows to its full potential size or is somewhat smaller. In an average 10 gallon tank, if well cared for and not crowded, they can grow up to about 4 inches (10 cm), while in a larger uncrowded tank they can grow larger generally reaching about 7 or 8 inches (17.78 - 20.32 cm). If kept in a spacious pond they can reach over 12 inches (30+ cm).

They are primarily a reddish orange color, but they are also available in yellow, orange, white, and red. There are also a bi-color red/white combination and occasionally they are available with nacreous (pearly) scales, giving them a variegated color.

Comet Goldfish can and do naturally change color, but color changes are believed to be influenced by diet and the amount of light. Aquarists often report the reds and oranges of their goldfish changing to white. A fresh diet, along with good lighting but with shaded areas are suggested as the best way to maintain the original coloration, but are not always successful.

Other types of Comet Goldfish include the Sarasa Comet. This variety has long flowing fins and is characterized by a red-and-white coloration that holds a resemblance to a koi color pattern called 'Kohaku'. The Tancho Single-tail Comet is a silver colored variety with a red patch on its head.

  • Size of fish - inches: 4.0 inches (10.16 cm) - Comet goldfish housed in small aquariums will have stunted growth that will limit their size to four inches. In larger aquariums they will reach about eight inches, and up to twelve in a pond.
  • Lifespan: 14 years - Comets have a natural life span of up to 14 years, though possibly longer if kept in optimal conditions.

Fish Keeping Difficulty

Comet Goldfish are some of the hardier species of goldfish. They are very undemanding of water quality and temperature. They can do well in a goldfish aquarium, or even a pond as long as the environment is safe and their tank mates are not competitive.

Many people will keep goldfish in an aquarium with no heater or filtration, but for the best success provide them the same filtration, especially biological filtration, that other aquarium residents enjoy.

  • Aquarium Hardiness: Very Hardy - Take care that you invest in quality stock. Although comets can be bought very inexpensively as feeder fish, this stock will often be disease ridden and certainly not bred for longevity.
  • Aquarist Experience Level: Beginner

Foods and Feeding

Since they are omnivorous, the Comet Goldfish will generally eat all kinds of fresh, frozen, and flake foods. To keep a good balance give them a high quality flake food everyday. To care for your goldfish, feed brine shrimp (either live or frozen), blood worms, Daphnia, or tubifex worms as a treat. It is usually better to feed freeze-dried foods as opposed to live foods to avoid parasites and bacterial infections that could be present in live foods.

  • Diet Type: Omnivore
  • Flake Food: Yes
  • Tablet Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet
  • Vegetable Food: Some of Diet
  • Meaty Food: Some of Diet
  • Feeding Frequency: Several feedings per day

Aquarium Care

Regular weekly water changes of 1/4 to 1/3 is strongly recommended to keep these fish healthy. Snails can be added as they reduce the algae in the tank, helping to keep it clean.

  • Water Changes: Weekly

Aquarium Setup

Setting up a goldfish aquarium in a manner that will keep your fish happy and healthy is the first step to success. The shape and size of the aquarium is important and depends upon the number of goldfish you are going to keep. These fish need a lot of oxygen and produce a lot of waste.

Good filtration, especially biological filtration, is very helpful in maintaining the water quality of the aquarium. Filtration systems remove much of the detritus, excess foods and waste. This in turn helps to keep the tank clean and maintain the general health of the goldfish.

Goldfish are freshwater fish, but they have some tolerance for slightly brackish water. The salinity level for goldfish must be kept low, below 10% with a specific gravity of less than 1.002.

  • Tank parameters to consider when choosing a goldfish aquarium:
    • Tank size
      Fifteen gallons is the absolute minimum required to house a Comet Goldfish. For more than one it's better to start with a 20 - 30 gallon tank, increasing the size of the tank to provide 10 gallons for each additional goldfish. Providing a large amount of water per fish will help dilute the amount of waste and reduce the number of water changes needed.
    • Tank Shape
      Always provide the maximum amount of surface area. A large surface area of water will help minimize goldfish suffering from an oxygen shortage. Surface area is determined by the shape of the tank. For example an elongated tank offers more surface area (and oxygen) than a tall tank. In an oval or round shaped tank the middle offers more surface area than filling it to the top.
    • Number of fish
      For juveniles a general rule of thumb is 1 inch of fish (2.54 cm) per 1 gallon of water. But this rule only applies to young fish and is not adequate as they grow. Larger gold fish consume much more oxygen than young fish so maintaining this formula for growing fish will stunt them, and can contribute to disease and even death.
    • Fish size and growth
      To allow for proper growth, either buy fewer fish than the maximum number or be prepared to get a larger tank. To prevent stunted growth and other health problems, don't overstocking the aquarium.

Goldfish are a cold water fish and will do best at temperatures between 65 - 72° F (18°- 22° C). The Comet Goldfish are one of the most hardy varieties and can tolerate temperatures a few degrees above freezing, as long as the cooling drops only a few degrees a day. A quick temperature drop can kill them, so if you live in a very cold climate a heater is advisable.

Provide a gravel substrate to help create a natural and comfortable environment for your fish. You can add some decor, but make sure that all ornamentation is smooth with no protruding points or sharp edges. Smooth rocks or driftwood should be used sparingly if at all. Aquarium plants would be the best choice of aquarium decor for goldfish, but unfortunately these fish are diggers. Consequently live plants may be uprooted. Artificial plants make a good substitute and silk plants are safer than plastic ones.

Most aquariums come with a cover that includes lighting. A cover for the tank is desirable as it reduces evaporation and though they are not prone to jumping, on occasion some gold fish will jump out. Lighting is not essential for goldfish, but does make the aquarium a nice show piece and lighting will help if you have live plants.

  • Minimum Tank Size: 15 gal (57 L) - Fifteen gallons is the recommended minimum to house this active fish. It has high oxygen requirements, produces a lot of waste, and will have stunted growth if it is kept in a smaller aquarium.
  • Suitable for Nano Tank: Sometimes - A Nano tank is fine as long as it is 15 gallons or more, a larger tank will be needed for a community.
  • Substrate Type: Any - A medium sized gravel works best.
  • Lighting Needs: Moderate - normal lighting
  • Temperature: 65.0 to 72.0° F (18.3 to 22.2° C) - Goldfish can tolerate colder temperatures, but this is the optimum range for activity and longevity in Goldfish.
  • Range ph: 6.0-8.0
  • Hardness Range: 5 - 19 dGH
  • Brackish: Sometimes - Goldfish are freshwater fish, but they have some tolerance for slightly brackish water. Any salinity for must be kept low, below 10%, a specific gravity of less than 1.002.
  • Water Movement: Moderate
  • Water Region: All - These fish will swim in all areas of the aquarium.

Social Behaviors

Goldfish are very social animals and thrive in a community. Not only are they a great community fish but they are great scavengers as well. It is really not necessary to add other scavengers or other bottom feeders to the aquarium when you have goldfish.

Most fancy goldfish will thrive in both freshwater and tropical aquariums as long as there are no aggressive or territorial fish in the tank. Some good tank mates for fancy goldfish are the Chinese Blue Bitterling and the Northern Redbelly Dace. Comet Goldfish can be kept with other varieties of elongated goldfish, such as the Common Goldfish and the Shubunkin, and they also do fine with Koi.

  • Venomous: No
  • Temperament: Peaceful - Although rarely aggressive, Comet Goldfish are very active and might annoy tankmates that prefer a peaceful environment.
  • Compatible with:
    • Same species - conspecifics: Yes
    • Peaceful fish (): Safe
    • Semi-Aggressive (): Threat
    • Aggressive (): Threat
    • Shrimps, Crabs, Snails: Safe - not aggressive
    • Plants: Threat - Goldfish will eat many kinds of aquatic plants, and their constant search for food can end up uprooting plants that they don't eat.

Sex: Sexual differences

During the breeding season the male has white prickles, called breeding tubercles, on its gill covers and head. Seen from above a female will have a fatter appearance when she is carrying eggs. It is impossible to sex Goldfish when they are young and not in breeding season, but generally the male is smaller and more slender than the female.

Breeding / Reproduction

Goldfish are egg layers that spawn readily in the right conditions. See Breeding Freshwater Fish - Goldfish for more information on breeding Goldfish.

  • Ease of Breeding: Easy

Fish Diseases

Goldfish are subject to the same diseases as tropical fish. A couple of the more common problems are Ich, Swim Bladder Disease, and external parasites including flukes, lice and anchor worms. For more in-depth information about goldfish diseases and illnesses, see: Goldfish Care; Fancy Goldfish and Goldfish Diseases.

Availability

The Comet Goldfish is readily available in fish stores and on-line, and is inexpensive

References

Author: David Brough CFS
Lastest Animal Stories on Comet Goldfish


brady - 2014-07-13
Fun, active, clean, hearty, colorful cheap fish.

Reply
Katie - 2010-03-04
Just as this website explains above, comet goldfish require filtration and aeration just like other aquarium fish. They shouldn't be kept in bowls. A full grown comet will require a minimum of a 30 gallon tank. Even a small 1 inch goldfish shouldn't be kept in anything smaller than 2 gallons, and that's for only one comet TEMPORARILY! If you're really wanting to keep a fish in a bowl, I would recommend a betta. Although they actually prefer a warmer temperature (78-82 degrees F), they usually live at room temperature with no problem. They will not require filtration as long as you change out the water once weekly (make sure you are using "conditioned" tap or well water or spring water, and make sure it is at about room temperature so as too not shock the fish). Bettas are also different from most fish in that they do not require aeration. Bettas actually breathe from the air/water surface. Keep in mind, however, that you can only have one betta per bowl/tank. *If you get a female betta (shorter fins), you can sometimes keep more than one per bowl/tank, but keep in mind that should the fish begin to fight, you will have to have a second container to separate them.

  • Gia - 2014-07-05
    Actually bettas are quite a bit more demanding than gold fish, they DO NOT do well in bowls they need at minimum a 1.5 gallon tank and 2+ Gallons is better. They need filtration and some time of temp regulator (heater). To put any fish in a bowl with out a heater and filtration is cruel and shouldn't be done. Source: betta breeder for 15 years.
Reply
Olly L - 2014-04-15
I am going to get one of these for my 15 gallon as it is minimum tank size. Thanks Dr.Jungle

Reply
Brittany - 2014-03-29
I got a Comet Goldfish 3 days ago. I know it is a male. I named him Gil. He is is the only fish I have at the moment. I have a question. I have had been told that your fish can like being a pet like a cat or dog. Is that good for a fish? If yes could I try with him. He is the only fish I have at the moment. I also want to get a place for him to hide, I have silk plants, but I would like something he can go in to hide from my cat. My cat and him are cool but my cat is a bit of a hunter. So I think he likes more hiding spots. What kind of things are good for him?

  • ILA McDougal - 2014-04-06
    If you go to pet smart look for the SpongeBob decorations and you'll see the pineapple and tiki house those might help.
Reply