Common Goldfish (single-tail)

Carassius auratus

Common Goldfish (single-tail) (Carassius auratus) — Intermediate care, Peaceful, under Goldfish. Minimum tank in the app: 48 US gal min; aim for 50–72°F and pH 6.5–8. The Common Goldfish is ideal for aquarists who appreciate resilient, long-lived species that thrive in spacious environments.

Common Goldfish (single-tail) (Carassius auratus) in a planted freshwater aquarium
Care levelIntermediate
TemperamentPeaceful
Min tank size48 US gal min
pH range6.5–8
Temperature50–72°F
Max size11.8 in (30.0 cm)
Captive lifespan10–25 years
SchoolingNo

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

East Asia

  • East & Southeast Asia

Regional colours match the stocking calculator’s origin map.

Common Goldfish (single-tail) Tank Setup

Aim for a spacious layout with ample swimming room, complemented by subtle decorations that provide hiding spots without obstructing movement. Strong filtration is essential to handle their significant bioload, and a sandy or fine gravel substrate can mimic their natural foraging environment, while moderate lighting can enhance their colors without causing stress.

What Do Common Goldfishs Eat?

These fish are omnivorous and will compete for food, particularly when offered sinking pellets or flakes. Monitor feeding to ensure all individuals receive adequate nutrition, as their slower feeding habits can lead to competition with faster species.

Common Goldfish (single-tail) Tank Mates

Goldfish are highly compatible with similarly sized, non-aggressive species that share similar environmental needs. Ideal tank mates include larger-bodied species like certain types of barbs or calm loaches. Avoid small, fast-swimming fish that may be viewed as food and ensure ample space to prevent territorial disputes, especially in smaller groups.

Are Common Goldfishs Good for Beginners?

We rate this as intermediate. Budget time for testing, maintenance, and watching behaviour if the water looks fine but the fish do not. Aquarists often underestimate the tank size required for goldfish, leading to stunted growth and health issues. Neglecting filtration needs is another common error, as their high waste production can quickly degrade water quality, resulting in diseases and stress.

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