Discus
Symphysodon aequifasciatus (species complex)
The 'king of the aquarium': a disc-shaped Amazon cichlid in countless bred colours that needs warm, soft, very clean water.
Key facts
- Body length
- 5.5 in without fins
- Minimum tank
- 80 gallons
- Group
- 5+
- Temperament
- Peaceful, shy
- Care level
- 4 / 5
- Lifespan
- Not well documented
- Diet
- Discus granules, frozen bloodworm and brine shrimp
- Origin
- Amazon basin, South America
- Hardier than22%
- Bigger than68%
- Calmer than68%
Water: their range vs yours
Discus tank mates
- Neon tetraGets along in shared water.Good mates
- Harlequin rasboraGets along in shared water.Good mates
- OtocinclusGets along in shared water.Good mates
- Cherry shrimpGets along in shared water.Good mates
- BettaGets along in shared water.Good mates
- AngelfishGets along in shared water.Good mates
- Black neon tetraGets along in shared water.Good mates
- Black widow tetraGets along in shared water.Good mates
- Blood parrot cichlidGets along in shared water.Good mates
- Blue dolphin cichlidGets along in shared water.Good mates
- Bristlenose plecoGets along in shared water.Good mates
- Bronze coryGets along in shared water.Good mates
- Fancy guppyFancy guppy outcompetes the slow-eating Discus for food; target-feed to make sure it eats.Risky
- Amano shrimpAmano shrimp outcompetes the slow-eating Discus for food; target-feed to make sure it eats.Risky
- Chinese algae eaterChinese algae eater eats slow fish: Discus (SF: присасывается к бокам крупных соседей, объедая слизь).Risky
- Clown loachClown loach outcompetes the slow-eating Discus for food; target-feed to make sure it eats.Risky
- Common plecoAmazon sailfin catfish (common pleco) outcompetes the slow-eating Discus for food; target-feed to make sure it eats.Risky
- Convict cichlidConvict cichlid (aggressive) will bully the peaceful Discus.Risky
- Panda corydorasPanda corys can't take discus heat.Avoid
- Tiger barbTiger barbs harass slow discus.Avoid
- Iridescent sharkIridescent shark can eat Discus: prey body depth 11.2 cm ≤ mouth 32.5 cm.Avoid
- OscarOscar can eat Discus: prey body depth 11.2 cm ≤ mouth 12.3 cm.Avoid
- African clawed frogAfrican clawed frog should only be kept in a single-species tank.Avoid
- Marbled crayfishMarbled crayfish should only be kept in a single-species tank.Avoid
How we check
The numbers the tank model uses for discus: water as ideal and tolerated ranges, bioload from adult mass, space, flow and how they act on other species.
- Standard length
- 14 cm (SL)
- Adult mass
- 157.21 g
- Bioload at 25 °C
- 17.67 BU
- Min. water
- 255 L net
- Min. footprint
- 120 × 45 cm per group
- Min. height
- 45 cm
- Group
- 5+ (best 6)
- Swims in
- middle
- Flow
- low
- Body / fins
- compressed disc, normal fins
- Diet type
- micropredator
- Fin nipper
- none
- Sensitive to
- nitrate
Sources: Seriously Fish: Symphysodon aequifasciatus · FishBase: Symphysodon aequifasciatus
Care notes
Discus come from Amazon floodplains with soft, acidic water, and aquarium fish are bred hybrids of several wild species. They are shy, slow eaters that feel safest in a group.
Keep five or more in a mature tank around 75 gallons with a 4-foot footprint at 79–86°F, with frequent water changes since they are sensitive to nitrate. Most other fish cannot take that heat, and fast eaters will outcompete them at feeding time.
Questions
What size tank does a discus need?
At least 80 gallons (255 litres of water after decor). Adults reach about 5.5 inches without fins.
How many discus should be kept together?
Keep at least 5, ideally 6 or more: fewer feel exposed and hide or turn nippy.
What water do discus need?
79–86 °F, pH 5–7 and 0–5 dGH. Discus come from Amazon basin, South America.
How long do discus live?
Not well documented with good care.
What fish can live with discus?
Good tank mates include Neon tetra, Harlequin rasbora, Otocinclus, Cherry shrimp and Betta. Each is checked both ways for size, fin nipping, temperament, territory and shared water.