Calcule le NH3 toxique à partir de l'ammoniac total, pH et température. Sache quand ton taux d'ammoniac est vraiment dangereux pour les poissons.
Total ammonia exists as two forms: toxic unionized ammonia (NH3) and relatively harmless ionized ammonium (NH4⁺). At higher pH and temperature, more ammonia exists as the toxic NH3 form. A reading of 1 ppm total ammonia at pH 8.0 is far more dangerous than at pH 7.0.
NH3 above 0.02 ppm causes stress and long-term damage. Above 0.05 ppm is acutely dangerous and can kill sensitive fish. Even 0.01 ppm over extended periods can impair gill function and immune response.
As temperature rises, the equilibrium shifts toward NH3 (unionized form), increasing toxicity. A tank at 30°C has roughly twice the toxic NH3 fraction as the same tank at 20°C with identical total ammonia and pH.
Do an immediate 25–50% water change. Stop feeding. Check for dead fish or decaying matter. Add ammonia-neutralizing conditioner (e.g., Prime). Improve filtration. Reducing pH slightly also reduces NH3 toxicity.
Use an API Ammonia test kit or digital ammonia meter. Reagent kits measure total ammonia (NH3 + NH4⁺). This calculator then tells you what fraction of that total is the dangerous NH3 form based on your pH and temperature.