TLF AccuraSea Refractometer Calibration Solution

Two Little Fishies Accurasea 250 ml Refractometer Callibration Solution is a Seawater Reference Solution. It's the only calibration solution of its kind made from real seawater. Its pure natural seawater micron filtered and UV sterilized then adjusted with reverse osmosis water to match the standard S 35 or 53 ms/cm at 25C (77F). Use it to accurately calibrate your seawater refractometers and to check the accuracy of other hydrometers.