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Main features of Red Sea’s Seawater Refractometer include:
Directly reads the absolutesalinity ofseawaterat25°C/77 0F ( No need for seawater or temperature compensation factors)
Specifically designed for the ionic content of seawater (NSW) for more accurate salinity measurement (industry standard refractometers are calibrated for salt brine ).
Calibrated for seawater (NSW) at 25oC/77oF, the normal temperature range for reef aquariums
(most standard refractometers are calibrated at 15oC/59oF ).
Easier to read, higher resolution display, focussed to the relevant range for reef aquariums of up to 40ppt
Includes Integrated Automatic Temperature Compensation (ATC) for accurate measurement at standard ambient temperature.
Red Sea’s Refractometer display
The PPT scale on Red Sea’s Seawater refractometer is calculated using an algorithm for seawater and therefore will give a reading of the Absolute Salinity of seawater. The PPT scale on regular salinity refractometers are calculated using an algorithm for Brine. Using a Brine refractometer for Seawater will give an error of approximately 1.5ppt in the salinity reading.