🧴Water care for a Killifish: 20 to 24°C, pH 6 to 7
Killifish : Soft, slightly acidic water without elevated nitrates, often softened with RO water. Constantly warm temperatures noticeably shorten its lifespan.
🩺 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 6 cm as an adult depending on the species, 20 to 50 L depending on the species, water between 20 and 24 °C. A lively, colorful little surface fish, often kept species-only with one male and two or three females. A formidable jumper requiring a gap-free lid; its lifespan varies greatly by species, often only 1 to 3 years.
The Killifish’s water: its real parameters
For a Killifish, water quality comes in numbers: 20 to 24°C on the thermometer, pH within the 6 to 7 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 as you go and filter media rinsed in tank water, never under the tap: chlorine sterilises your filter.
Health: what stalks the Killifish
In the Killifish, watch for: velvet (oodinium) in unstable water and sensitivity to elevated nitrates. But the golden rule holds for the whole tank — nearly all disease starts in degraded water or chronic stress, and you ALWAYS test the water before reaching for medicine. Well kept, a Killifish lives 1 to 3 years.
Frequently asked questions
What water parameters for a Killifish?
20 to 24°C, pH 6 to 7, zero nitrites and nitrates under 25 mg/L — checked with drop tests, not by eye.
How often should a Killifish 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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