Care Guide for Fancy Goldfish – Housing, Feeding, and More

Fancy fish (Carassius auratus), are beautiful freshwater fish of the carp family. They come in many shapes, colors and other traits. Unlike common goldfish with their single tails and streamlined physiques, fancy goldfish have flowy double tails and slow-moving, egg-shaped bodies that require special considerations. This care sheet answers some of the most frequently asked questions we get about these beloved water piggies.

What size tank does Fancy Goldfish require?

Appropriate aquarium size can be a point of contention among goldfish owners, but in general, we recommend 20 gallons of water volume per goldfish, with at least 10 gallons added for every other goldfish. One goldfish will outgrow a 20-gallon aquarium in five to six years. This will mean that you will have to change the water frequently to keep the tank clean. Whereas if you house five or six goldfish in a 60- or 70-gallon aquarium, the tank maintenance schedule will be more manageable.

Goldfish tanks are bigger than ever, so make sure they have as much space as possible.

In addition to water volume, consider the dimensions of the tank. A squatter tank that has more water surface is better for goldfish. This is in contrast to a narrow, tall tank. Goldfish originated in China, where they were first introduced. They use large, wide bowls that have lots of surface area. This gives them more swimming space, and allows for more oxygen exchange. Bottom line, get the largest tank possible and keep it clean.

Do Fancy Goldfish Need a Heater?

Goldfish are known as cold water fish because they can live in temperatures of 50-70degF (10-21degC). This means that in a home with heating and air conditioning, there is no need to use a heater inside the aquarium because goldfish can live at room temperature. Many people who live in mild climates keep their fish in outdoor ponds all year.

Although you might not require a heater for goldfish, it is important to filter the water. Goldfish are very picky and produce lots of waste. Common choices include hang-on-back filters and sponge filters that have gentle flow and are easy to maintenance. You should ensure the filter creates surface agitation that increases oxygenation for your fish.

What should I feed my Fancy Goldfish?

If you feed them lots of lower quality food, they tend to contain more indigestible materials, and therefore the tank will get dirty faster and require more water changes. If you feed a “cleaner” diet with frozen foods or duckweed, the aquarium requires less maintenance, and the fish display more vibrant coloration. We love to feed our goldfish frozen brine shrimps, high quality pellets and Repashy Gel Foods.

Overfeeding your goldfish may cause you to feel bloated. Give them two small meals per day.

Overfeeding is more common than underfeeding. So don’t spoil your goldfish by giving them too many meals, even if they begging for food. A smaller meal twice per day is better than a big one once per day because goldfish can become bloated easily. There’s an Internet adage is that goldfish should never be given floating foods because they will swallow too much air and cause bloat, but we have regularly fed floating foods for more than a decade and never had problems with any of our fish.

Why is my Goldfish tank cloudy?

It could be caused by several things. It could be caused by beneficial bacteria rapidly reproducing because of increased fish waste. The best course of action is to patiently wait a week without making any drastic changes to the aquarium, and the bacteria cloud will eventually disappear on its own.

Water that is cloudy from particulate floating in it may need to be changed. A clogged filter will not remove any debris. Use water test strips that are easy to use and change the water every time the nitrates exceed 50 ppm. It is a good idea to change 30 to 50% of the water each time. Once the nitrates reach 50 ppm again you should monitor this and create a weekly or monthly schedule. As the fish grow larger, they produce more waste. It may be worth buying a bigger tank, moving them outside, or giving them up to someone who has more space.

To extend the time between water changes and provide greater enrichment for the fish, we like to use live aquarium plants as decor. We have an entire article on safe plants for goldfish, as they have a love for vegetables and will churn up substrate to search for food. This list mainly includes rhizome plants such as anubias, ferns, and rocks that can be attached so they are not easily removed.

Robust, easy-to-grow aquarium plants can help absorb nitrogen waste compounds and reduce your maintenance frequency.

Why is my Goldfish acting strange? Is It Okay?

The funny and quirky creatures known as goldfish have unique personalities. We recommend checking on your goldfish every day, whether they are active or lethargic, and that you keep them fed at least once per day.

You should look out for signs of ich, such as large wens that have grown over the eyes and white spots. Make sure everyone’s getting along and the fish aren’t breeding too aggressively with each other. You’ll be able to keep your tank healthy by monitoring the temperature, pH, nitrates, and other factors at least once per week, even during holidays.

Goldfish keeping is frowned upon because of the stigma they carry. Beginners will often buy them and get the wrong advice. They may also end up in small water bowls with no water changes. Goldfish are fairly hardy compared to more sensitive species, but you should still treat them with the same care you would give any other fish (e.g., regularly gravel vacuum the aquarium, service the filter, and test the water quality). There are two main points to keep in mind: a) they prefer cooler temperatures, and b) their size means they require a larger tank.