Comet Goldfish (Carassius auratus) doesn’t naturally exist in the wild. They were selectively bred from Common Goldfish in the United States during the 1880s.
Despite their origins in a controlled setting, their care requirements are similar to their wild counterparts. These fish can adapt to a wide range of water conditions due to their hardy nature, making them suitable for both outdoor ponds and indoor aquariums.
Given their active nature and need for space to swim, many fishkeepers prefer to keep Comet Goldfish in outdoor ponds along with Koi Carp. The outdoor settings provide ample space for their active lifestyle, enabling them to swim and explore freely.
Comet Goldfish Appearance and Lifespan
Comet Goldfish, also known as Comet-tailed Goldfish, are eye-catching due to their vibrant color and lively behavior. They physically resemble Common Goldfish but are somewhat slimmer. Comet Goldfish are commonly found in yellow, orange, red, white, and red-and-white colors. The red color is often prominent on the tailfin and dorsal fin and occasionally on the pelvic fin. Their long, deeply forked tail fin sets them apart from other Goldfish breeds.
Comet Goldfish grow quite large. In a 15-gallon aquarium, these fish typically grow to about 4 inches long. In a larger, unconfined tank, they can reach an impressive 7 to 8 inches. If kept in a pond, they can grow over 12 inches in length.
These fish thrive and are most resilient in pond environments since they can withstand extremely cold water temperatures, even below freezing.
Comet Goldfish have a relatively long lifespan. They usually live between 5 to 14 years. With ideal conditions, they can live even longer. Some owners have reported their Comet Goldfish living for 15 to 20 years with the right care.
Physical Characteristics of Comet Goldfish
Comet Goldfish are easily identified by their distinct physical features. They’re popular for their attractive colors and sleek bodies, making them an active and sought-after aquatic species.
These fish are slim and slender, with vibrant color variations that include yellow, orange, red, white, and red-and-white combinations. The most distinctive feature of Comet Goldfish is their elongated, deeply forked tail fin.
Behavioral Characteristics of Comet Goldfish
Comet Goldfish are dynamic and energetic creatures, known for their active swimming and agility.
They’re social creatures and do well in groups of their kind. They can also coexist peacefully with other non-aggressive fish species, adding to the vibrancy and visual appeal of an aquarium.
Comet Goldfish display a curious behavior of foraging, often seen digging in the substrate of their tanks. This makes gravel or sand an ideal substrate choice for their habitat. They may even move pebbles around, reflecting their natural habit of rearranging their surroundings. They also have a tendency to uproot plants in the process of their exploration.
Setting up An Aquarium for Comet Goldfish
To set up a perfect aquarium for your comet goldfish, follow these steps:
- Start with a tank that holds at least 75 gallons (284 liters). This size is necessary for these active swimmers. If you plan to add more fish, add an extra 50 gallons (190 liters) per fish.
- Comet Goldfish produces a lot of waste. So, a good filtration system is essential. A canister filter is recommended for maintaining water quality.
- Choose a suitable substrate. Sand is often preferred because it allows your Comet Goldfish to forage without the risk of choking on large pieces of gravel. If you prefer gravel, opt for quartz gravel or small pea gravel (2 to 3mm).
- Decorate the tank with care. Avoid sharp-edged decorations that can harm their delicate fins. Incorporate silk and live plants such as Anubias, Java Fern, and Hornwort. These provide a natural element for your pet to enjoy.
- Maintain the temperature between 60°F to 72°F (16°C to 22°C). Ensure proper aeration by using an air pump to provide sufficient oxygen in the tank.
- For lighting, standard LED or fluorescent lighting is sufficient.
- Feed your Comet Goldfish high-quality pellet or flake food. Supplement their diet with live, frozen, or freeze-dried foods like brine shrimp, earthworms, and bloodworms. Occasionally include blanched vegetables like peas or cooked carrots for variety.
- Regularly monitor water parameters and perform water changes as needed to maintain a healthy environment for your fish.
Comet Goldfish Diet
Feeding your Comet Goldfish appropriately is crucial for their healthy development. These omnivorous fish need a diet that mimics their natural food sources, which includes both plant and animal matter.
In the wild, they consume insects, larvae, algae, water plants, snails, and crustaceans. In a home aquarium, try to replicate this diet to ensure they receive all necessary nutrients.
You can use high-quality prepared foods like Omega One Goldfish Pellets or Northfin Goldfish food as a base for your fish’s diet. These are made with key ingredients such as whole krill and spirulina algae.
Supplement your fish’s diet with blanched vegetables like peas or small zucchini pieces occasionally. These provide essential fiber that helps digestion. You can also add variety to their diet with frozen blood worms, daphnia, brine shrimp, or tubifex worms. If your Comet Goldfish lives outdoors, they may enjoy eating worms, insect larvae, or water insects.
However, be cautious when using live feed since it can introduce parasites and bacteria into your tank. Always source live food from trusted suppliers and remove it from the supply water before feeding it to your fish.
Feeding your Comet Goldfish two to three times a day is sufficient. Also, be careful not to overfeed. Only give them the amount of food they can eat within two or three minutes. Overfeeding can lead to health issues.
Ideal Tank Mates for Comet Goldfish
Comet goldfish are known for their lively nature and need a spacious tank of at least 30 gallons. They can coexist with several types of fish, including the Common Goldfish, despite its known fin-nipping habit and preference for cooler water.
Shubunkin Goldfish and White Cloud Mountain Minnows are also good companions for Comet Goldfish. Despite their small size, White Cloud Mountain Minnows are quick and provide a playful environment.
Zebra Danios and Cherry Barbs are other suitable tank mates. Cherry Barbs produces a lot of waste. So, frequent water changes are necessary to maintain the water quality.
Koi can also coexist with Comet Goldfish because they share similar needs regarding food and environment. They also grow quite large and have longer lifespans similar to Comet Goldfish.
Frogs and certain Snail species can also be good companions, contributing to a clean and diverse environment. Dojo Loach is another ideal tankmate for Comet Goldfish.
However, avoid slow-swimming Fancy Goldfish since they can cause collisions and injuries. Also, Comet Goldfish tend to eat very small fish and Shrimp, making them unsuitable tank mates.
How to Breed Comet Goldfish?
Breeding Comet Goldfish needs careful planning and several steps.
Comet Goldfish are known for their messy spawning habits, scattering eggs and sperm throughout their environment. For indoor systems, it’s necessary to provide them with corresponding day and night light cycles and a gradual increase in water temperature to mimic springtime breeding conditions found outdoors.
Here’s a guide to help you succeed in breeding Comet Goldfish.
The first step is to identify the gender of the fish. This can be done once they reach breeding age, between 1 ½ to 2 years old. Males develop tubercles on their face and gill plates, as well as on their bodies and fins. They have a slim, concave area between their ventral and pelvic fins. On the contrary, females have a fuller body and a flat or rounded space between their ventral and pelvic fins.
The next step is to set up a suitable breeding environment. Comet Goldfish grows to over 10 inches, so a single fish needs a tank of at least 55 gallons. It’s not advisable to keep more than 2 in a tank due to their high bioload.
Also, Comet Goldfish prefer cold water. So keep the tank in a cool room. Avoid overly warm or heated habitats since this can cause nerve damage. In terms of diet, they’re omnivores and mainly eat plant matter and algae.
Breeding Comet Goldfish is challenging and is best done in outdoor ponds. If you want to do this at home, you’ll need a separate tank to keep parents away from eggs.
To initiate spawning, expose your fish to a month of lower temperatures and reduced light for less than 8 hours a day. Feed them high-quality food like frozen items, vegetables, herbivore flakes, and pellets to encourage breeding.
Finally, spawning is triggered by the female releasing pheromones. The male will then produce milt and chase the female to lay eggs. He fertilizes the eggs by spraying his milt onto the roe.