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Common goldfish

Freshwater Intermediate Peaceful

Common goldfish grows to about 11.8 in and needs a tank of at least 79 US gal. Here's how to keep it healthy and what it lives well with.

Quick facts

Water type
Freshwater
Group
Cold-water
Difficulty
Intermediate
Temperament
Peaceful
Swims
All levels
Adult size
11.8 in
Minimum tank
79 US gal
Min swim length
47.2 in
Group size
2+ together

Water parameters

Temperature
50–75 °F
pH
6.5–8
Hardness
5–19 dGH

Tank & care

Common goldfish is a shoaling species — keep a group of at least 2 so they feel secure and show natural behavior. Kept alone or in twos they tend to turn shy, stressed or nippy.

Give it at least 47.2 in of swimming length and hold the water around 50–75 °F. Match any new species to these ranges before adding them.

Plan a tank with this fish

Use the stocking calculator to see how many Common goldfish your tank can hold and whether your planned tankmates are compatible — it's anchored to your net water volume and footprint.

Open the stocking calculator Calculate tank volume

Figures are conservative hobby-consensus estimates for planning. Individual fish vary — always research a species and watch how yours behave.

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