Comet Goldfish: Full Care Guide

The Comet Goldfish is one of the most popular breeds of goldfish. They have been in the aquarium scene for many years. Many aquarists are captivated by the beauty of their forked tail and vibrant color.

In this care guide, you will learn, how to care for them, what to feed, tank requirement, size, water parameters, and tank mates.

Category Rating
Care Level:Medium.
Temperament:Peaceful and Playful.
Color Form:Yellow/Orange.
Lifespan:4-14 years.
Size:Up to 12 Inches.
Minimum Tank Size:50 gallon.
Tank Set-Up:Freshwater, Cold, Planted.
Compatibility:Other Goldfish varieties.

Overview of Comet Goldfish

They have been with us since the end of the 1800s. They have taken the aquarium hobby by storm and this shows no signs of stopping. Their vibrant colors caught the many aquarist’s eyes. They can live up to 14 years and even more and grow up to 12 inches in length.

The Appearance of Comet Goldfish

They look similar to standard Goldfish. There are some distinct physical traits upon closer inspection especially the tail. A normal Goldfish have short and stiff tails but the Comet Goldfish have flowy forked tails.

They got their name because of their flowing golden tail which resembles a comet.

The Comet Goldfish have a singular forked tail with two tips rather than a twin- tail with four tips like other species. They have a dorsal fin, a thin anal fin, and two lengthy pectoral fins. All of their fins are semi-transparent and can take on the same coloration as the rest of the body.

There is a lot of color variant of Comet Goldfish. The most common variants found in aquariums are Yellow, Orange, White, and Red. You may also see the brown specimen as well.

Size of Comet Goldfish

They can grow up to 12 inches long. If you put them in the wrong or small tank they will not grow up to 12 inches. If you put them in a big space with a healthy environment they will grow their full.

The Behavior of Comet Goldfish

Comet Goldfish are fast swimmers and will spend lots of time exploring their surroundings. They are fun to watch. Sometimes they will quickly be darting across your tank, which is why you need plenty of space.

They are not aggressive fish, so they should not show signs of aggression toward other fish. Do not put small tank mates because they can be easily be mistaken for food.

You may see aggression during their feeding session. You can place feed at both sides of the tank to reduce competition for food.

The Tank Requirements of Comet Goldfish

The Comet Goldfish is a descendant of wild carp known as the Prussian Carp. Those carp are native to Asia and lived in slow-moving bodies of water such as rivers. They are also found in lakes, large ponds, and ditches that were below the water level.

If you want to keep more than 4 together, you are going to need a pond.

If you want them in your aquarium, you should get a rectangular-shaped one to provide them with plenty of space to swim in.

Tank Size of Comet Goldfish

The minimum tank size for them should be 50 gallons. The recommended tank should 75 gallons tank if possible. That is for a single fish.

If you plan on keeping a group, you will need to add about 50 gallons of space for each additional fish.

Water Parameters

  • Water Temperature: 50o-70oF.
  • pH Level: 6.0-7.5
  • Water hardness: 5-19 dKH


You can use gravel substrate to create a nice foundation for the environment. Make some hiding places and caves in your aquarium.


Plenty of live plants are a must. Live plants can be a source of food for the fish. The plants will help to oxygenate the water.


They produce a lot of waste, so you are going to need to invest in a filter that is powerful enough to keep ammonia levels low. Use hang-on back or canister filter for the tank.

Diet for Comet Goldfish

They are omnivores so they will eat both meat and plants/vegetables. You can feed the high-quality dried food. A varied nutritious diet is crucial for their bright coloration. For meat sources, you can feed them:

  • Small Insects.
  • Worms.
  • Bloodworms.
  • Mosquito larvae.

In terms of plants and vegetables you can feed them:

  • Lettuce.
  • Broccoli.
  • Algae.

You should aim to feed them 2-3 times per day and only give them what they can consume in less than 2 minutes. After this, you should remove the remaining food from the aquarium.

Tankmates for Comet Goldfish

They do not make good tank mates. This is not because they are aggressive, and it is due to these two main reasons:

  • They live in freshwater but they are not tropical. You would not able to keep them with other popular freshwater fish, as the warm water is too hot for them.
  • They tend to consume lots of food, so other fish in the tank is at risk of being malnourished.

Here are some good tank mates to consider:

Hey, I am Shuvradeb Biswas a content writer. Fishkeeping is my hobby. There are many problems I faced during my first fishkeeping. So, I made the blog to help new fishkeepers.

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