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What Size Tank Does a Discus Need?

Minimum tank: 55 gallons

A Discus (Symphysodon aequifasciatus) grows to about 8 in (20.3 cm), so the practical minimum is a 55-gallon aquarium. A pair or small group is typical, so leave a little extra room for tankmates.

Single fish or pair55 gallons
Comfortable group55 gallons
Community setup65 gallons+

Bigger is easier: more water dilutes waste and holds temperature and pH steady. See stocking ideas for a 55-gallon tank or try the stocking calculator.

Frequently asked questions

What is the minimum tank size for a Discus?

At least 55 gallons.

Can a Discus live in a smaller tank?

Going under 55 gallons stresses the fish, worsens water quality and shortens its life — not recommended.

More on this species: Discus full care guide · tank size · temperature · pH & hardness · tank mates