Species profile

Blue Discus

Symphysodon aequifasciatus var. "Blue"

Common names: Blue Discus, Royal Blue Discus, Royal Discus

Colour varietyCichlids

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Adult size

Up to 15 cm

Typical adult length 12–15 cm.

Up to 15 cm

Countries of origin

Good fit for your tank?

Good fit for

A tall tank of 350 L or more with a group of six, so no discus is bullied or shy
Water held steady at 28 to 30 Â°C and pH 5.5 to 6.5, with big weekly water changes
A calm tank with sand, wood, and quiet tankmates that do not steal food

Think carefully if

You are new to fishkeeping: discus stunt and fall ill quickly when water slips
You keep cool-water or boisterous fish, which cannot share its warm, quiet tank
You want it in an ordinary community tank: fast feeders will starve it, and the heat suits few other fish

A wild discus with heavy, iridescent blue striping across the body. Wild discus need warm, soft, acidic water and more care than domestic strains.

Appearance and Identification

A wild discus with heavy, iridescent blue striping across the body. Fish striped from head to tail are sold as Royal Blue.

Wild blue striping looks different from the turquoise lines of domestic fish. Ask where a fish was collected. Discus with very similar genes are sold under different names, and one seller's name may not match another's, so judge a fish by its pattern, body colour, pepper (fine black speckling) and eye colour.

Sexes are hard to tell apart by eye. Mature males may be larger with a broader head, but the breeding tubes and spawning behaviour are more reliable.

Tank Requirements

Suggested filter: About 700–1,050 litres an hour
Suggested heater: About 350–525 W for this tank
Minimum tank volume: 350 litres
Minimum tank length: 150 cm
Minimum group size: 5
Recommended group size: 6
Activity level: Moderate
Flow preference: Low
Planting preference: Moderately planted
Hiding places: Yes
Lid recommended: Yes
Jumping risk: Low

Keep a group of at least five or six in a tall, mature tank with excellent filtration, calm flow, open feeding space and vertical cover. Quarantine all new fish.

Behaviour and Tankmates

A calm, shoaling cichlid that can become shy, bullied or underfed in too small a group.

Groups form a pecking order. Pairs separate to spawn and may need their own breeding tank.

Breeding pairs defend a vertical surface and the area around it. Outside breeding, aggression is mainly social ranking.

Use calm, warm-water tankmates that do not nip fins or take all the food. Small fish and shrimp may be eaten.

Check tankmates for this species

Water Parameters

Temperature: 28–30 °C
pH: 5.5–6.5
GH: 1–3
Stability importance: Critical

Wild fish need softer, more acidic water than domestic strains.

Parameter caveat

Stable water matters more than an exact number. Do not mix fish from very different water without slow acclimation.

Feeding

Diet types: Insectivore, Omnivore
Feeding frequency: Daily
Preferred foods: Quality discus pellets or granulesA good daily staple. Feed small amounts and remove what is not eaten, because leftovers foul warm water quickly.
Frozen bloodworm and brine shrimpOffer often for variety and condition.

An omnivore that does well on varied pellets and frozen foods.

Feed several small meals a day, and remove uneaten food quickly in warm water.

Breeding

Breeding type: Egg Layer, Substrate Spawner
Breeding difficulty: Difficult
Brood or egg count: Commonly 100 to 400 eggs
Incubation: 3 days
Parental care: Biparental care
Baby foods: Skin mucus from the parentsFry feed on this for about their first four weeks. Parent-raised fry survive better than fry raised without it.
Newly hatched brine shrimpAdd as the fry grow and start to swim away from the parents.

Pairs lay on vertical surfaces. Both parents guard the eggs and produce a skin mucus that feeds the fry for about their first four weeks.

Habitat and Origin

Geographic origin: Amazon Basin, Brazil, Colombia, Peru, South America
Natural habitat: Clearwater, Floodplain, Slow River
Aquarium contexts: Breeding Aquarium, Large Freshwater Aquarium, Planted Aquarium
Audience level: Advanced

Classification

Profile type: Colour variety
Genus: Symphysodon
Family: Cichlidae
Species group: Cichlids, Discus, Fish, South American Cichlids
Previous scientific names: Symphysodon haraldi, Some authors treat the blue discus as this separate species.

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Good fit for your tank?

Good fit for

Think carefully if

Appearance and Identification

Tank Requirements

Behaviour and Tankmates

Water Parameters

Feeding

Breeding

Habitat and Origin

Classification

Have you kept this species?

Other Discus

Brilliant Blue Discus

Brown Discus

Calico Discus

Checkerboard Discus

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