Guardian™ Serim® Water Hardness Test Strips
Serim Water Hardness Test Strips take a semi-quantitative measurement of the total hardness in water. The test strips should be used to check water hardness at the post-softener stage. Color blocks are located at 0, 10, 25, 50 and 120 ppm (0, 0.6, 1.5, 3, 7 gpg).
Six bottles of 50 test strips per box.