15-Stage Shower Water Filter System with Vitamin C - 1 Filter + 2 Replacements hot tub tester 3 dKH ±5% of reading Extends probe life easy MA917B/1 water filter monitor

15 Stage Shower Water Filter System with Vitamin C 1 Filter + 2 Replacements hot tub tester 3 dKH ±5% of reading Extends probe life easy MA917B 1 water filter monitor 3 dKH ±5% of reading at 25 °C Alkalinity Marine Method Colorimetric Method Calcium Marine Range 200 to 600 ppm Calcium Marine Resolution 1 ppm Calcium Marine Accuracy ±6 % of reading at 25 °C Calcium Marine Method adaptation of the Zincon Method Magnesium Range 1000 to 1800 ppm (as Mg²+) Magnesium Resolution 5 ppm Magnesium Accuracy ±5% of reading at 25 °C Magnesium Method Adaptation of the Colorimetric EDTA Method using calmagite indicator pH Range 6 Auto on when placed in nutrient water