Red Sea pH/alkalinity test kit includes an accurate titration test for KH and a colorimetric test for pH for monitoring these essential parameters in all marine aquariums to an accuracy of 0.2 ppm. Performs 100-tests. It range is 7.6ppm-8.6ppm. Marine care program ph./alkalinity test kit Includes an accurate titration test for KH and a colorimetric test for pH for monitoring These essential parameters in all marine aquariums Its accuracy of 0.2 ppm; performs 100 tests It range is 7.6ppm-8.6ppm