Low Hardness Test Kit – LH-2011
- Fill the pipette to the 10 ml mark with sample.
- Add the water to the clean flask.
- Add contents of one Low Hardness (I) reagent to the flask and swirl to dissolve. A blue color indicates the hardness is 0 mg/L. If a red color develops, proceed to step 4.
- Fill the titration pipette with 1 mL of Low Hardness (II) reagent.
- Add the reagent slowly and swirling untill untill the color changes from red to blue. If 1 mL is not enough, repeat step 4 & 5. Read off the measurement value (V, mL) from the pipette.
- Calculate the results. Hardness = V x 20 (mg/L, as CaCO3).
- Rinse flask with deionized water before the test.
- The pH must be within the range 6-9. Adjust if necessary, with NaOH or HCl.
- When pipetting, if there are air bubles in the pipette, pull and push the piston repeatedly with the suction port immersion in the liquid.