Fancy goldfish care guide

Plan a tank with fancy goldfishSee all tank mates

Fancy goldfish quick facts

• Cold-water species: no heater needed in most homes.
• Long fins attract fin nippers.

Tank setup

Plan on 20 gallons (76 L) for one fancy goldfish and 10 gallons (38 L) more for each extra, so two do well in 30 gallons (114 L). A long, wide tank with lots of surface beats a tall, narrow one. Use smooth decor and smooth gravel, sand or a bare bottom, because their eyes and long fins tear easily on sharp edges.

How many fancy goldfish in a tank?

The smallest common tank that suits fancy goldfish is a 20 gallon. Here is roughly how many fit in each size when they are the only fish, based on adult size and waste output. Leave room if you want tank mates.

Water parameters

Keep them at about 18–23 °C (64–73 °F), pH 6.5–8.0 and moderately hard water. Most homes need no heater, but avoid sudden temperature swings. They make a lot of waste, so use a filter with good surface movement but gentle flow, test nitrate weekly and change 30–50% of the water when it climbs.

Best tank mates for fancy goldfish

These popular species share fancy goldfish' water needs and temperament. See the full list of 8 good matches.

• Malaysian trumpet snail

  2.5 cm (1 in) · 20–27°C (68–81°F)

• Platy

  6 cm (2.4 in) · 20–26°C (68–79°F)

• White cloud mountain minnow

  4 cm (1.6 in) · 16–22°C (61–72°F)

• Hillstream loach

  6.5 cm (2.6 in) · 20–24°C (68–75°F)

• Peppered corydoras

  6.5 cm (2.6 in) · 20–25°C (68–77°F)

• Variatus platy

  6 cm (2.4 in) · 18–25°C (64–77°F)

• Checkerboard barb

  5 cm (2 in) · 20–25°C (68–77°F)

Avoid keeping fancy goldfish with

• Angelfish: They need different temperatures: Fancy goldfish 18–23°C (64–73°F), angelfish 24–29°C (75–84°F).
• Betta fish: They need different temperatures: Fancy goldfish 18–23°C (64–73°F), betta fish 24–28°C (75–82°F).
• Cherry shrimp: Fancy goldfish eats small shrimp like cherry shrimp.
• Dwarf gourami: They need different temperatures: Fancy goldfish 18–23°C (64–73°F), dwarf gourami 24–28°C (75–82°F).
• Tiger barb: Tiger barb is a well-known fin nipper and will shred the long fins of fancy goldfish.
• Blood parrot cichlid: They need different temperatures: Fancy goldfish 18–23°C (64–73°F), blood parrot cichlid 24–27°C (75–81°F).

Feeding

Feed a quality sinking goldfish pellet or gel food as the staple, plus frozen brine shrimp, daphnia and blanched peas or greens. Give two small meals a day that they finish within a couple of minutes. Sinking food helps round-bodied types avoid gulping air at the surface, and overfeeding quickly fouls the water.

Behavior

Peaceful, social and always hungry. They swim slowly, so keep them with other fancy goldfish rather than fast commons or comets, which take their food and sometimes nip their fins. They eat shrimp, fry and fish small enough to swallow, and they dig up or eat soft plants. Fast cool-water fish such as white cloud minnows and hillstream loaches can work in larger tanks.

Breeding

In spring, males grow small white bumps on the gill covers and front fins, and females look fuller. Spawning often follows a cool spell and a slow warm-up, with males chasing females hard through the plants. Adults eat the eggs, so move plants or spawning mops with eggs to another tank. The eggs hatch in a few days.

Tips from experienced keepers

• Don't mix fancy goldfish with commons or comets. The faster fish eat first and may nip long fins.
• Choose smooth decor. Telescope-eye and bubble-eye types injure their eyes easily.
• Tie anubias and java fern to wood or rock. Goldfish eat or uproot most soft plants.
• Skip the bowl. Even one fancy goldfish needs a filtered tank of about 20 gallons (76 L).
• Feed in more than one spot when you keep several, so the slowest fish gets its share.

Sources

We checked these references when writing this page. Values are for healthy long-term keeping, not survival limits. Last reviewed 2026-10-13. See our editorial policy.

• aquariumcoop.com
• aquariumcoop.com
• ornamentalfish.org
• kb.rspca.org.au