🧴Water care for a Betta: 24 to 28°C, pH 6.5 to 7.5
Betta : It appreciates soft to neutral, stable water with a 20 to 30 percent weekly change. Its long fins are fragile: watch for any sign of fin rot and avoid sharp decorations.
🩺 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: 6 to 7 cm as an adult, 20 L minimum for a single male, heated water between 24 and 27 °C. Spectacularly territorial: two males together means a guaranteed fight — hence the name fighting fish. A labyrinth fish that breathes air at the surface: the tank needs a lid (it jumps) and gentle flow — those long fins tire quickly.
The Betta’s water: its real parameters
The Betta’s water contract has four clauses: 24 to 28°C, pH between 6.5 to 7.5, zero detectable nitrite, nitrates capped at 25 mg/L. 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 Betta
The Betta watch-sheet: fin rot in poor water and constipation and obesity from overfeeding. 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 Betta lives 3 to 5 years.
Frequently asked questions
What water parameters for a Betta?
24 to 28°C, pH 6.5 to 7.5, zero nitrites and nitrates under 25 mg/L — checked with drop tests, not by eye.
How often should a Betta tank get water changes?
10 to 20% weekly, water brought to temperature, filter rinsed only in tank water. Consistency beats volume.
The guides that apply to you
- Cleaning your aquarium with soap or detergent: the mistake that can kill your fish
Why you should never clean an aquarium with soap or detergent: toxic residue, safe alternatives and good maintenance habits.
- Dropsy in Fish: Symptoms, Causes and Treatment
Pinecone scales, swollen belly... dropsy is a serious sign, not a disease in itself. How to recognise it and act fast.
- Chlorine and Chloramine in Tap Water: Why They Kill Your Fish
Chlorine and chloramine in tap water are toxic to fish and to your biofilter. Why you must condition water before every water change or new tank setup.
- Axolotl Water Parameters: Temperature, Nitrite and Flow
What water parameters does an axolotl need? Cool temperature, zero ammonia and nitrite, gentle flow: the benchmarks for a sensitive amphibian.