Tube test for the determination of Total hardness. Precise rapid tests for all kind of water and waste water samples. Time-saving and reliable analysis together with Macherey-Nagel NANOCOLOR photometers. Measuring range: Calcium - 10–100 mg/L Ca²⁺, Magnesium - 5–50 mg/L Mg²⁺, Total hardness - 0.2–3.6 mmol/L , Total hardness - 1.0–25.0 °e , Total hardness - 20–350 mg/L CaCO₃Manufactured by Macherey-Nagel