🧴Water care for a Corydoras: 22 to 26°C, pH 6 to 7.5
Corydoras : Its barbels get damaged on sharp or dirty substrate: fine sand and regular vacuuming are essential. Beware of salt or copper treatments, which it tolerates poorly.
🩺 Our hygiene and health advice stays general: it never substitutes for an examination by a veterinarian, the only person qualified to advise on your animal.
In short: 4 to 7 cm as an adult depending on the species, around 100 L for a group of 6, water between 22 and 26 °C. A peaceful, gregarious bottom fish, it sifts the sand in a group and gets stressed with fewer than six companions. Its barbels wear down on sharp or dirty substrate: fine sand is mandatory, and take care with salt and copper, which it tolerates poorly.
The Corydoras’s water: its real parameters
For a Corydoras, water quality comes in numbers: 22 to 26°C on the thermometer, pH within the 6 to 7.5 window, nitrites at zero, nitrates under the 25 mg/L bar. 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 — the bottom is the Corydoras’s home zone, respect its landmarks and filter media rinsed in tank water, never under the tap: chlorine sterilises your filter.
Health: what stalks the Corydoras
The Corydoras watch-sheet: barbel erosion on unsuitable substrate and white spot disease in stressed fish. 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 Corydoras lives 5 to 10 years.
Frequently asked questions
What water parameters for a Corydoras?
22 to 26°C, pH 6 to 7.5, zero nitrites and nitrates under 25 mg/L — checked with drop tests, not by eye.
How often should a Corydoras 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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