Discus
Symphysodon aequifasciatus · family Cichlidae
Also: Blue Discus, Green Discus, King of the Aquarium
Parameters
- Temperature
- 28–31 °C
- pH
- 6–7
- Hardness
- 1–8 °dGH
- Tank volume
- from 250 L
- Maximum size
- up to 20 cm
- Group size
- min 5, ideal 6
- Temperament
- Peaceful
- Swimming zone
- Middle
- Difficulty
- Expert
- Lifespan
- 10–15 years
Description
The Discus (Symphysodon aequifasciatus) is universally revered as the 'King of the Freshwater Aquarium' for its laterally compressed disc-shaped body and iridescent patterns. Native to quiet Amazonian floodplains, this peaceful schooling cichlid demands ultra-clean, soft, acidic water (pH 6.0–7.0, GH 1–8) and elevated temperatures of 28–31 °C (82–88 °F).
Care
Keep a minimum shoal of 5–6 Discus in a 250+ liter (65+ gallon) aquarium. Use a high-capacity UV canister filter (such as the Sunsun HW-3000), a precision titanium/electronic heater set to 29–30 °C, and RO water remineralized to 100–180 ppm TDS. Perform 30–50% weekly water changes to keep nitrates below 15 ppm and prevent Hexamita (hole-in-the-head). Read our full guide: /articles/discus-fish-water-parameters-temperature-guide.
Feeding
Feed specialist high-protein Discus granules enriched with astaxanthin, spirulina flakes, freeze-dried blackworms, and clean frozen bloodworms or brine shrimp 2–3 times daily (4–5 times for juveniles).
Breeding
Monogamous pairs spawn on vertical ceramic breeding cones in very soft water (pH 5.8–6.5, TDS 60–100 ppm). Free-swimming fry feed directly on the nutrient-rich epidermal mucus secreted on both parents' flanks.
Compatibility
- Rummy-Nose Tetra
Hemigrammus rhodostomus
Родостомусы отлично переносят 28–30 °C и служат идеальным индикатором чистоты воды в аквариуме с дискусами. / Rummy-Nose Tetras thrive at 28–30 °C and act as ideal dither fish and water-quality bio-indicators for Discus.
Good - German Blue Ram
Mikrogeophagus ramirezi
Апистограммы Рамирези любят такую же тёплую (28–30 °C) и мягкую воду, занимая придонный ярус. / German Blue Rams share identical warm (28–30 °C), soft, acidic water requirements and occupy the bottom zone peacefully.
Good - Yellow Lab Cichlid
Labidochromis caeruleus
Африканские цихлиды требуют жёсткой щелочной воды и слишком агрессивны для спокойных дискусов. / African cichlids require hard alkaline water and are far too boisterous for peaceful Amazonian Discus.
Avoid
FAQ
- Why do Discus need 28–31 °C (82–88 °F) water?
- Below 27 °C, a Discus's metabolism and gut immunity drop sharply, making them highly susceptible to intestinal flagellates (Hexamita) and bacterial infections.
- Can I keep a single Discus fish?
- No. Discus are hierarchical schooling cichlids that become stressed and stop eating if kept alone; always keep a group of at least 5–6 individuals.
Goldie editorial team
Practising aquarists with a combined 30+ years of experience · Biologists and editors, fact-checking against FishBase and Seriously Fish · Every piece is reviewed by a qualified ichthyologist before publication
Scientific board — ichthyologists and veterinarians
Ichthyologists and veterinarians with university degrees · Reference FishBase, Seriously Fish and peer-reviewed literature · Sign every reviewed article with their credentials shown
Sources
- FishBase: Symphysodon aequifasciatus · FishBase · 2026-05-22
- Seriously Fish: Symphysodon aequifasciatus · Seriously Fish · 2026-05-22