A proper formulated buffer should function in such a way that the corrective measures results in a long lasting effect and should not upset the pH of the system. The alkalinity or carbonate hardness should be kept as stable as possible requiring highly sensitive and accurate means for testing.
The Salifert KH/Alk test is very straightforward. It measures in sufficient small steps of 0.1 meq/L or 0.3 dKH with a sharp color change. This makes detection of important yet small change possible.
The kit can perform approx. 100 - 200 measurements.