Care at a glance
Temperature28–30 °C (82–86 °F)
pH6.0–7.0
Min tank55 gal (208 L)
Adult size20 cm
Lifespan8–10 years

Most people buy a Discus on looks alone, then wonder why it sulks. The fish is fine; the setup around it usually is not. The Symphysodon aequifasciatus Discus is a long-time favourite for a reason, but it has specific needs that generic "community fish" advice misses.

At a glance

Minimum tank55 gallons (209 L)
Temperature28 to 30 °C
pH range6.0 to 7.0
Adult size15 to 20 cm
Lifespan8 to 10 years
Group sizea group of 6+

Where it comes from

In the wild the Discus lives in slow, vegetated waters where cover is everywhere and currents stay gentle. Recreating that means planting densely, keeping the filter flow soft, and avoiding bright, open tanks that leave the fish exposed. Stable water matters more than perfect parameters.

Tank setup

Start with at least 55 gallons and a mature, cycled filter — see our alternanthera reineckii for beginners guide before you buy. A sand or fine gravel substrate, a few driftwood branches and a carpet or mid-ground plant mass give the fish somewhere to retreat. Keep nitrates under 20 ppm with a weekly 22% water change.

Feeding

Feed a varied diet: a quality flake or micro-pellet as the base, topped up with frozen or live foods two or three times a week. Offer only what the fish clears in about 1 minutes, once or twice daily. Overfeeding is the single most common cause of water-quality swings.

A mistake everyone makes

Adding a Discus to a brand-new tank is the classic error. An uncycled tank spikes ammonia to 0.5 ppm within days and the fish pays for it. Cycle first, stock lightly, and let the group size build up gradually.

Good tank mates

Peaceful, similar-sized neighbours work best. Avoid fin-nippers and anything large enough to swallow the Discus. A planted community with a solid bucephalandra guide in the mix tends to settle quickly.

Reading the numbers

Target 28 to 30 °C and a pH near 6.0 to 7.0; ammonia and nitrite must read 0 ppm and nitrates stay under 20 ppm. Test weekly and do a 24% water change so the Discus never rides a parameter swing.