FISH OF THE WEEK | Common Goldfish

by Toledo Goldfish Admin May 16, 2025

Fish of the Week | COMMON GOLDFISH

Common Goldfish (Carassius aurastus) are one of the most well known fish in the world and as their name suggests are very common. With their bright orange color they are a popular choice for aquariums and ponds. They are sometimes referred to as common goldfish or comet goldfish. Common goldfish tend to have shorter finnage, while comet goldfish will sometimes have longer finnage like sarasa comet goldfish. We will explore why Comet goldfish are a popular choice for aquariums by covering key aspects of their life. We will explain their lifespan, how big they can get, and how fast they grow.

Common goldfish are not just a delightful addition to your aquarium; they are a fascinating species that can bring joy and beauty to your aquatic environment. Understanding their growth, lifespan, and compatibility with other fish can enhance your experience as an aquarist. Let’s dive into the captivating world of comet goldfish!

History behind Common Goldfish

Goldfish come from China and were domesticated over 1,000 years ago. They were originally bred for ornamental ponds and indoor display. Different types of goldfish have been selectively bred from the common goldfish to create a variety of distinct goldfish types. Goldfish were originally only owned by royalty or those high in society but became a sign of wealth and prosperity in Asian cultures. Goldfish became popularized in the United States in the 1800s as they gained popularity and quickly became a sought after pet.

Goldfish Appearance

Common goldfish have a long torpedo-shaped body with a short tan shaped tail. They are typically orange, red, or gold but can also be bronze or white with a variation of color patterns including those colors as well. They can grow up to 10-12 inches in size and can live as long as 10-15 years with good care.

Common vs. Comet Goldfish

These orange goldfish are very similar but also very different. Common goldfish tend to have shorter finnage, while comet goldfish will sometimes have longer finnage like sarasa comet goldfish. Comet goldfish are the sportier version of common goldfish with larger tails and sometimes more energy.

TOLEDO GOLDFISH | Comet vs common goldfish

Goldfish Diet

Goldfish are omnivores and like a variety of foods. Good quality goldfish pellets floating or sinking will work. You can supplement your goldfish diet with treats like blanched vegetables (peas, lettuce, and spinach) as well as live/frozen foods like bloodworms. Make sure to feed the treats sparely as to not over feed your goldfish. In most outdoor systems they will take advantage of the natural food in the pond as well.

Goldfish Behavior & Compatibility?

Common Goldfish are usually peaceful active swimmers and very social, making them excellent community fish. They are best kept with other single-tailed goldfish (like shubunkins, comets, and sarasa goldfish) but can also be kept with koi as well. We suggest keeping similar sized goldfish and koi together to keep them from picking on each other. It's essential to keep in mind that both goldfish and koi are active swimmers and will appreciate a spacious tank to explore and play in.

Tips for Caring for Goldfish

When caring for Common Goldfish , it's crucial to make sure they have good water quality and depending on your system, make sure to perform regular water changes. Additionally, ensure they have plenty of space to swim and explore, as well as a balanced diet to keep them healthy and thriving. Goldfish are omnivores and will eat flakes, pellets, and any natural food sources in your pond. Do remember to not overfeed as it can cause water quality and swim bladder problems.

When you first receive your fish, don't be alarmed if they don't come up and feed right away as some fish take time to adjust to their new system and learn to come up and feed. Feed training can take a couple weeks, but both goldfish and koi are very food motivated and typically pick it up quickly. We recommend being consistent in the time and place you feed so they can learn your routine and learn to associate you with food. We also suggest feeding in the morning or evening as the fish are more active at these cooler times of day.

A Few More Quick Tips for Common Goldfish

Prioritize water quality first - bad water kills goldfish faster than anything else
Protect in outdoor ponds from predators like herons - common goldfish are colorful so easy targets!
Feed a varied diet - this keeps their immune system strong and coloration vibrant
In ponds offer shade, depth, and hiding spots to protect your goldfish from predators

Fun Facts About Common Goldfish

The longest living goldfish on record lived 43 years!
Common goldfish are smarter than they are given credit for and can learn routines and remember simple tasks like pushing buttons or swimming through hoops for a reward.
Goldfish can see infrared and ultraviolet light which is more than humans can see!
The color of a goldfish can fade or deepen depending on diet, light exposure and genetics.
Color Changes - Goldfish are born a muted brown color as fry and it takes 60-90 days to gain their true color and they will continue to change a lot within their first year.

Common Goldfish are great fish for both beginners or experienced fish keepers! There is lots of variety in color or go with a most common solid orange. You can not go wrong with whatever goldfish color you choose. Goldfish are sure to bring joy and beauty to your water system for years to come!