Calculating in-situ pH is a complex process. Optimal accuracy calls for coefficients from a meticulous calibration process, as well as temperature, pressure, and salinity from a high-quality CTD. The SeapHOx V2 and Deep SeapHOx V2 can only meet their accuracy and resolution specs when all of these are available.
Fortunately, Sea-Bird Scientific has refined our calibration process, and the 37-SMP-ODO CTD provides excellent CTD data quality, ensuring quality pH data for moored deployments. In most cases, the SeaFET V2, SeapHOx V2, Deep SeapHOx V2, and UCI software are all making this calculation in the background. However, in rare cases, CTD data may not be reaching the SeaFET V2, resulting in a NaN value for pH External. When this happens, it’s handy to know how to reprocess the raw data from the ISFET to salvage your data. Read our latest application note to learn how.