LaMotte Insta-Test 4 Plus, Free Chlorine, Bromine, Alkalinity, pH, Total Hardness Testing Chlorine, Bromine, Alkalinity, pH, Total Hardness. The Insta-TEST 4 Plus pool and spa strip measures Chlorine 0-10 ppm, Bromine 0-20 ppm, Total Alkalinity 0-240 ppm, pH 6.2-9.0, and Total Hardness 0-800 ppm. The test strip is a 1-dip method designed to match the way strip users actually test water Now with French, Spanish, and English instructions The bottle has a molded desiccant liner, which protects the strips from moisture and UV light.