🧴Water care for a Discus: 28 to 30°C, pH 6 to 7
Discus : One of the most demanding species for water quality: very low nitrates, remineralized RO water and 25 to 50 percent weekly changes, even more for juveniles. Any lapse quickly shows in its color and appetite.
🩺 The health watchpoints on this page are for information only: only a veterinarian can examine your animal and make a diagnosis.
In short: 15 to 20 cm as an adult, 300 L minimum for a group of 5, very soft water between 28 and 30 °C. A gregarious, shy cichlid that forms a group hierarchy and gets outcompeted at feeding time if too harassed. The most demanding for water quality: very soft, acidic, at 28-30 °C, with an RO unit and frequent water changes essential.
The Discus’s water: its real parameters
Temperature of 28 to 30°C, pH of 6 to 7, undetectable nitrites and nitrates under 25 mg/L: that is the contract. A drop-test kit (NO2, NO3, GH, KH, pH) beats any strip — and the nitrogen cycle, three to four weeks before any fish, is non-negotiable.
Water changes and tank upkeep
10 to 20% of the volume weekly, with water pre-heated to tank temperature: thermal shock stresses more than imperfect water, gentle substrate siphoning as you go and filter media rinsed in tank water, never under the tap: chlorine sterilises your filter.
Health: what stalks the Discus
The Discus watch-sheet: hexamita and hole-in-the-head in imperfect water and white spot disease in fragile juveniles. Before any treatment, the reflex is a water test — pouring medicine into loaded water is treating the fever by breaking the thermometer. Well kept, a Discus lives 10 to 15 years.
Frequently asked questions
What water parameters for a Discus?
28 to 30°C, pH 6 to 7, zero nitrites and nitrates under 25 mg/L — checked with drop tests, not by eye.
How often should a Discus tank get water changes?
10 to 20% weekly, water brought to temperature, filter rinsed only in tank water. Consistency beats volume.
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