Family: Cichlidae
A peaceful omnivore cichlidae from Brazil — advanced care.
A Cichlidae species: Symphysodon aequifasciatus lives mid-water swimmer; keep 5+ over clear streams, rivers and still waters. Peaceful. Adults reach 9.6–13.7 cm. It is one of the aquarium-kept Symphysodon species we profile, alongside Symphysodon tarzoo.
It pushes ornamental-fish aesthetics to the limit: a disc-shaped body, metallic blue-green-red striations, and a graceful hovering swim. It's also famously demanding — the more vivid the fish, the more delicate. It's the high-skill trade of the hobby.
Not the parameters themselves but the stability: 26–30 °C with swings under 1.5 °C, water changes 2–3 times weekly, high oxygen, zero ammonia. Meet these and they thrive; miss them and you get internal parasites, white-stringy feces and wasting fish.
Wild discus eat bottom-dwelling invertebrates. In captivity, beef-heart mix (beef heart + shrimp + vitamins + spirulina, frozen) is the gold standard, backed by quality discus pellets. Bloodworms alone unbalance nutrition and trigger enteritis.
Their native habitat is the Amazon floodplain, flushed daily with fresh water — they're evolved for new water. Changes of a quarter to a third, 2–3 times weekly, drive appetite, growth and parasite resistance. Laziness with water changes is the number one discus killer.
Grow juveniles in groups of 5+ to spread aggression and encourage feeding. Paired adults need their own breeding tank — established pairs attack everything else. They're gentle in a community but get rammed by rowdy fish like parrots and oscars.
Classic internal parasites (capillaria) or bacterial enteritis. Fast for 2 days, then treat with metronidazole for 3 days while raising temperature to 30–32 °C to accelerate the parasite cycle. Prevention: quarantine every new fish and disinfect foods.
They're extremely sensitive to shipping stress. Float the bag 30 minutes to equalize temperature, then add small amounts of tank water every 10 minutes for over an hour. Keep lights off for 24 hours and don't feed on day one; offer a little food on days two and three.
Adults are 13 cm discs with real body mass — 137 L is the floor, 200 L or more preferred. They're high-metabolism fish, so understock rather than overcrowd: 5–6 adults in a well-sized tank look and grow far better than 10 crammed in.
Medium-strong light over a dark background shows their colors best, 8–10 hours daily. Dim light for juveniles reduces fright; boost blue and red spectrums during color development. Permanent darkness dulls them; harsh unshaded light stresses them.
8–10 years in captivity. Breeding is very achievable: bonded pairs lay eggs on a vertical cone (plant pot or PVC pipe) and guard the clutch, feeding the fry with skin secretions — the famous discus milk, one of the most fascinating behaviors in the hobby.