Discus

Behaviour and habits

The discus is the most spectacular of the freshwater cichlids, a tall, flat, disc-shaped fish that comes in brilliant colours and moves through the water with a slow, regal grace. It is peaceful and social, living in groups in the wild, and it does best in a group rather than alone. It is, however, genuinely demanding: it needs very warm, soft, acidic, exceptionally stable water and a mature tank, and it is unforgiving of the mistakes a beginner tends to make.

What to feed, and how often

A carnivore that wants meaty food — frozen bloodworm, mysis, prawn and a quality discus granule — fed several small meals a day rather than one large one. Variety and a steady supply of protein keep discus in colour and condition, and underfeeding or poor food quickly shows in their shape.

Water changes and maintenance

Change 30–50% weekly with warm, soft, acidic water matched very closely, because discus react badly to sudden changes. Keeping nitrate low and the parameters rock-steady is the heart of discus keeping, and it is not a fish for irregular maintenance.

Care and how easy it is

For experienced keepers only: it needs very warm, soft, acidic, stable water, a large tank, a group and a meticulous routine.

Common health problems

Sensitive to stress and poor water; prone to internal parasites, hole-in-the-head and bacterial infections.

If it gets sick

Quarantine and deworm new stock, keep the water pristine and warm, and treat early in isolation if a fish darkens or stops feeding.