pH test

Rinse the crucible and cap well with test water. Fill the crucible to the mark with test water. Add 5 drops of pH reagent. Cap the crucible and mix. Determine the pH value by comparison with the coloured targets. When comparing, hold the crucible without the cap 3 to 5 cm above the white area between the coloured targets and look for a colour-matched target when viewed from above. If the colour is between two targets, estimate the result within this range. Read off the value by turning the card with the targets optimally to the light (by a window, in sunny weather outside in the shade, etc.).