DUROGNOST® SR (0.5 / 0.25 °dH) limit value test kit

The Durognost SR Threshold Test Kit is a simple set for quickly checking whether water hardness levels fall within the range of 0.25 to 0.5 °dH.

Special liquid indicator in a dropper bottle for monitoring residual hardness in softened water, calibrated to the limit values of 0.5 and 0.25 °dH (8.9 and 4.47 ppm).

With the Durognost SR kit, you can easily determine whether your water falls within this very soft hardness range. The indicator powder changes colour as soon as the water hardness limit is reached or deviates from it. This gives you a clear result quickly. This set allows for approximately 250 analyses.

The kit is only suitable if you wish to check whether the water hardness is very low. If you require exact numerical values, this kit is not suitable.

Quick test without laboratory equipment

First, rinse the measuring tube with the water sample. Then fill the tube with the water sample up to the 5 ml or 10 ml mark.

Add one drop of indicator and mix it thoroughly with the water sample by gently swirling the tube. After approx. 30 seconds, the water sample will change colour.

Water sample colour:

• Green = softened water is fine
• Red = Regenerate the water softener

Please note: When comparing the result with the enclosed table, it is essential to take the selected sample volume (5 ml or 10 ml) into account.

Please read the enclosed instructions for use carefully before use.