Blue Discus - Symphysodon discus

Blue Discus (Symphysodon discus)

The Blue Discus is a stunning freshwater cichlid, admired for its rounded disc-shaped body, graceful swimming style and beautiful blue colouration. Discus are often called the “king of the aquarium” because of their elegant shape, calm presence and premium appearance. This species is best suited to a mature, warm, peaceful aquarium with excellent water quality, soft acidic conditions and calm tank mates. While peaceful by nature, discus are specialist fish and should be kept by aquarists who can maintain stable, high-quality water.

Common Name:
Blue Discus. Also commonly referred to as Discus, Blue Discus Fish, Heckel Discus, Red Discus or Pompadour Fish, depending on strain and supplier identification.

Scientific Name (Latin):
Symphysodon discus
Please note: Blue captive-bred discus strains may also be traded under Symphysodon aequifasciatus or Symphysodon spp. depending on bloodline and supplier.

Maximum Size:
Around 15–20 cm in captivity, depending on strain, diet, water quality and age. FishBase lists Symphysodon discus at around 12.3 cm standard length, while aquarium-kept discus are often measured including body depth and total length.

Water Type:
Freshwater

Origin / Natural Habitat:
Wild Symphysodon discus is native to the Amazon River basin in Brazil, including areas near the mouth of the Rio Negro and lower Abacaxis and Trombetas river regions. In nature, discus are associated with warm, slow-moving waters, submerged roots, fallen branches, flooded forest areas and soft acidic blackwater environments. Most blue discus available in the aquarium trade are captive-bred colour strains rather than wild fish.

Water Parameters:
Temperature: 27–30°C
pH Range: 5.5–7.0
Hardness: soft water preferred, ideally low to moderate hardness

Temperament:
Peaceful but specialist. Discus are calm cichlids that should be kept with gentle tank mates that will not bully them, nip fins or outcompete them for food. Avoid aggressive, fast-moving or boisterous fish.

Diet:
Omnivorous with a preference for small animal-based foods. It should be offered a varied diet including quality discus granules, soft pellets, frozen bloodworm, brineshrimp, mysis, daphnia, blackworm where suitable, and specialist discus foods. A varied diet helps support strong colour, condition and growth.

Minimum Tank Size:
A practical recommendation is at least 300 litres for a proper group, with larger aquariums preferred for long-term stability. A 120 cm aquarium or larger is strongly recommended, as discus need swimming space, stable water volume and room to establish a social hierarchy.

Behaviour & Activity:
This is a calm mid-water cichlid that should usually be kept in a group of at least 5–6 individuals unless maintaining a proven breeding pair. In groups, discus are more confident and display more natural behaviour, but they can still form hierarchies. They appreciate tall aquariums, gentle flow, shaded areas, wood, plants and open swimming space. Sudden movement, unstable water or aggressive tank mates can cause stress.

Aquarium Category:
Community Fish
This species is peaceful enough for a carefully planned specialist community aquarium. Suitable tank mates include Cardinal Tetras, Rummy Nose Tetras, peaceful Corydoras suited to warm water, Otocinclus in mature systems, small peaceful plecos and other calm soft-water fish. Avoid fin nippers, aggressive cichlids, large predators, very active barbs, cool-water fish and anything that cannot tolerate discus temperatures.

Special Requirements or Care Notes:
Discus require warm, very clean and stable water. Regular maintenance, excellent filtration, low nitrate and careful feeding are essential. They should not be added to immature aquariums or unstable systems. Captive-bred discus are generally more adaptable than wild discus, but they still need consistency and low stress. If keeping true Symphysodon discus / Heckel-type discus, softer, more acidic water and expert-level care may be required.

Suitable for:
Intermediate to experienced fishkeepers

Availability:
Common / occasional in trade as captive-bred blue strains; true wild Symphysodon discus forms are rarer and more specialist.

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Please note that Mother Nature is a wonderful thing, and variation in patterns and colours will occur — that is part of the unique beauty of these animals.