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

Fancy goldfish (Carassius aurantus) are gorgeous, selectively bred freshwater fish that can be found in a variety of colors, shapes and other characteristics. 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.

How big do Fancy Goldfish need a tank?

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.

Bigger is always better when it comes to goldfish tanks, so give them as much room as possible.

In addition to water volume, consider the dimensions of the tank. Goldfish prefer a squatter tank with more water surface area (and not a tall, narrow tank). The first goldfish were developed in China. Large, wide bowls have a lot of surface area. Bottom line: get the largest tank you can afford and make sure to regularly clean it.

Does Fancy Goldfish need a heater?

Cold water fish are goldfish because they can live at temperatures as low as 50-70 degrees Fahrenheit (10-21 degrees Celsius). 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. In fact, many people living in mild climates keep their goldfish in outdoor ponds year-round.

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?

They will eat less quality food and the tank will need 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. Our goldfish love Repashy gel foods, high-quality pellets and frozen brine shrimp.

Overfeeding your goldfish can lead to bloat, so consider giving them two small meals rather than one large meal 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. It is better to feed your goldfish smaller meals twice daily than one large meal per day. Goldfish are susceptible to bloating. The Internet says that floating foods should not be fed to goldfish as they can swallow too much air, which can cause them to bloat. However, we have been feeding floating foods for over a decade without any problems.

Why is my Goldfish tank cloudy?

There are many possible causes. If the tank is newly set up or you added a lot of new goldfish recently, the cloudiness could be a bacterial bloom as the beneficial bacteria is rapidly reproducing in response to an increase in 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.

A water change is recommended if the water becomes cloudy due to too much particulate in the water. The filter cannot effectively remove the debris from the tank if it has become clogged up. It is a good idea to get water test strips. We suggest changing the water when the nitrates reach 50 ppm. You can change 30% to 50% of your water at once, then monitor the time it takes for the nitrates levels to rise again to 50 ppm. Then, you can create a weekly, or monthly schedule, based on these results. 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. The list mostly consists of rhizome plants like anubias and ferns that can be attached to driftwood and rock so that they can’t be easily uprooted.

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?

Because goldfish are quirky and have individual personalities, their behavior can be very different from one fish to another. 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.

There’s a bit of a stigma around goldfish keeping because beginners will buy them, get the wrong advice, put them in a small bowl, and never do water changes… resulting in dying fish. 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). They prefer cooler temperatures than other fish in the pet shop and require larger tanks.