How to Take Care of Goldfish

The goldfish is the most commonly kept freshwater fish species across the globe. Proper goldfish care is essential to prolonging the life of your fish and keeping them happy.

Goldfish originate from China during the Tang dynasty, when a gold color mutation was observed in normal silver carp, and these gold individuals were selectively bred for generations. Goldfish were first introduced to Europe as a good luck charm in the 1600s and then were introduced to North America in the 1800s.

Common Goldfish vs. Fancy Goldfish

After generations of breeding, there are over 200 breeds of goldfish. Most of the goldfish available to pet parents are in one of two categories: common or fancy. Both types of goldfish can have numerous colorations, patterns, body shapes, and fin, eye, and tail types.

Common Goldfish

Common goldfish are small, fast feeder fish. They are single-tailed, meaning they have one caudal fin and one anal fin. Common goldfish varieties include:

• Comet goldfish

• Shubunkin

• Sarasa

Fancy Goldfish

Fancy goldfish are often bigger, slower, and bred to look more ornate than a common goldfish. Their number of fins differs based on their variety. Fancy goldfish varieties include:

• Nymph goldfish

• Tamasaba goldfish

• Wakin goldfish

• Fantail goldfish

• Ryukin goldfish

• Telescope goldfish

• Butterfly tail

• Pompom goldfish

• Lionhead goldfish

• Ranchu goldfish

• Celestial eye goldfish

• Bubble eye goldfish

How Long Do Goldfish Live?

The goldfish lifespan is anywhere between 10–15 years, sometimes even up to 20 years when kept in excellent conditions. Great goldfish care can extend the life of your pet significantly.

What Do Goldfish Need?

Tank Size for Goldfish

The tank size for a goldfish depends on the variety and the full-grown size of the fish. A goldfish, depending on type, can be housed in a habitat that provides about 20 gallons of water per fish. Some of the larger varieties of fish require a larger amount of space—up to 50–100 gallons.

Recommended tanks for goldfish include:

Goldfish Water Parameters

Good water quality is critical for keeping a goldfish healthy. The pH should range between 7–8.4 and you should test the water frequently.

If you have a freshwater fish tank, test it weekly with water quality test kits. Water aeration is vital to maintain oxygen levels within their habitat, which can be provided with an air pump and air stone. 

Do Goldfish Need a Filter?

Yes, filtration is important to help remove small particulates and houses a large portion of your biological filtration.

Do Goldfish Need a Heater?

Goldfish are most comfortable around room temperature (72–76 F). Depending on your room setting, you may or may not need a heater to keep your tank within this range. Heating a goldfish tank higher than this range will cause the fish to be very hungry and quickly foul their tank water.

What's the Best Temperature for Goldfish?

Goldfish are considered a cold-water fish species but can also be kept successfully at warmer temperatures.

Goldfish Plants and Decorations

Enriching your goldfish habitat with plants and decor makes it more naturalistic, but it’s important to remember that goldfish, as omnivores, may decide to eat or uproot some of the live plants. Some plant species that grow fast and can outgrow a hungry goldfish are:

• Vallisneria spp

• Anubias

• Java fern

• Cryptocoryne

Substrate can be used for goldfish habitats to make the bottom of the enclosure look more realistic. It is normal for goldfish to pick up their substrate and put it in their mouths. Some starter kits are available that will help get you started with your aquarium.

What Do Goldfish Eat?

Goldfish are predominately omnivores and can eat a sinking pellet. The food should provide about 30% protein for a goldfish.

Pelleted food can last longer than flake food. Take care when feeding flake food, as it often doesn’t sink. If a goldfish eats at the surface too much, they can develop buoyancy issues.

Additional dietary items that can be used as enrichment for goldfish include:

• Live or frozen brine shrimp

• Daphnia

• Krill

• Occasional vegetables like romaine lettuce

How Often Do You Feed Goldfish?

Adult goldfish can be fed once a day. Younger goldfish may need to be fed more often as they grow.

How to Clean a Goldfish Tank

Your goldfish will need their tank cleaned regularly. Your tank cleaning schedule will depend on the size of your fish tank, the total number of pet fish, and your filtration setup. Remember to always wash your hands before and after cleaning a tank.

Follow these steps on how to clean a fish tank:

1. Turn off your filtration, heater, and lighting.

2. Remove all decorations and place them in separate bucket or on a towel. Scrub them using a designated scrub brush and/or toothbrush.

3. Scrub sides of fish tank using an acrylic or glass scrub brush.

4. Place the siphon into your goldfish tank and start the flow into a bucket. Move the siphon up and down, taking in a small amount of substrate at each site. Allow it to circulate for a second or two, then lift the vacuum to break the siphon. Repeat across the entire bottom of your tank.

5. Remove your tank’s filter media (sponges, balls, floss, or rocks) and rinse them in the bucket of wastewater.

6. Rinse and fill your bucket with fresh tap water. Use your thermometer to ensure it is the correct temperature for your goldfish.

7. Add water conditioner per the manufacturer’s instructions. Add fresh water back into the main tank, then return the decorations, lights, heater, and filtration.

Goldfish Tank Mates

Many goldfish prefer to live by themselves and may attack other fish. It is OK for a goldfish to be by themselves, although they may interact well with friends—it all depends on the unique fish temperament.

If interested in keeping multiple fish, goldfish are best kept with more goldfish but can also live with other cold-water community fish, such as white cloud minnows.

Goldfish can make vibrant, entertaining pets for any family and can live a long, healthy life when given the right environment and care. They are a great beginner pet for anyone—even kids—and can be a rewarding companion for years to come.