TAN to un-ionized ammonia calculator.
Estimate the unionized NH₃ fraction and concentration from TAN, pH and water temperature.
TAN to un-ionized ammonia inputs
Planning tool only. Monitor water quality and animal behaviour, validate species-specific limits and follow the direction of a qualified aquaculture professional before changing stocking, feed, aeration or water chemistry.
Method: The calculator applies a temperature-adjusted acid dissociation relationship and uses pH to estimate the NH₃ fraction of TAN.
Inputs used: Total ammonia nitrogen (TAN) = 1 mg/L; pH = 8; Water temperature = 28 °C
Assumptions: The result uses the values, units and options shown in the input snapshot.
Scope and warnings: Planning tool only. Monitor water quality and animal behaviour, validate species-specific limits and follow the direction of a qualified aquaculture professional before changing stocking, feed, aeration or water chemistry. Rounding and excluded real-world terms can make an external result differ.
How this tan to un-ionized ammonia calculator works
The calculator applies a temperature-adjusted acid dissociation relationship and uses pH to estimate the NH₃ fraction of TAN.
A worked example
At the same TAN, warmer water and higher pH increase the calculated unionized fraction.
Can I use this as a treatment decision?
No. This is a freshwater planning equation with input and measurement uncertainty. Verify TAN, pH and temperature measurements and seek qualified help when fish show stress.
Calculations run on your device. Review your results before exporting or sharing them.
Measure TAN, pH and temperature together
Unionized ammonia depends strongly on pH and temperature. Enter values taken from the same water sample and time window for the calculation to be meaningful.
The equation is a freshwater estimate. Salinity, measurement error and fish condition matter, so treat a concerning result as a prompt for competent water-quality assessment.
Published by ToolMitra — methods and editorial approach.