The Pooltest 6 Photometer enables a complete water balance calculation, with tests for alkalinity, bromine, calcium hardness, chlorine, cyanuric acid and pH. It removes the need for choice or dilution by including both standard (0 – 5 mg/L) and extended range chlorine (0 – 10 mg/L). The Check Standards contain neutral density filters and can be used to verify that the instrument is within calibration and performing correctly.