CALDUR® Residual Hardness Test Set RG 100 – Limit Value Method
What is residual hardness measured for?
Residual hardness is a crucial parameter in the monitoring of water softeners and
ion exchangers. After water softening, it must be ensured that the hardness-causing minerals
(calcium and magnesium) have been largely removed to
prevent limescale deposits in downstream systems. The RG 100 test set checks for a limit value of 1.0 °dH (10 mg/l CaCO ) .
This limit value is particularly relevant for general water softening. Regular monitoring of the residual hardness is essential to
detect the exhaustion of the ion exchanger in time and to initiate regeneration before hard water
enters the system.
How does the test kit work?
The CALDUR® residual hardness RG 100 test kit uses the proven limit value method with a
color indicator. After adding a single drop of limit value indicator to the water sample,
the resulting color immediately shows whether the residual hardness is above or below the limit value. Green = residual hardness below 1.0 °dH – the water is sufficiently softened. Red = residual hardness above 1.0 °dH – the ion exchanger needs to be regenerated. This simple yes/no determination allows for extremely fast verification without complex
calculations or color comparisons.
Advantages of the CALDUR® test set
Extremely fast analysis in just 1 minuteImmediate detection of whether a limit has been exceeded or fallen below – ideal for frequent checks.
Extremely easy to use – only 1 drop requiredNo counting drops, no calculations – color shows the result directly.
Limit of 1.0 °dHIdeal for general water softening
250 provisions per setParticularly economical for regular routine checks
Clear color change from green to redClear visual distinction with no room for interpretation
Only one reagent is required.Minimal effort and no risk of confusion during implementation
Robust hinged lid box or compact folding boxOptimal protection of reagents – suitable for every application situation
Malaysia
