Test the salt level in the pool - Salt range: 0~9990ppm/10~100ppm; Check the salt concentration in saltwater pools and spas that use a salt chlorinator; It helps the salt chlorinator work more efficiently with the correct salinity value. Test the pool's pH level - pH: 0.00~14.00; Recommend a pH level between 7.2 and 7.8 depending on different types of pools (fiberglass, vinyl pools, and tile pools). When the pH value is back within range, for optimal performance and cleaner water. Test strips VS Digital meter - With strip tests, you have to guess which pool value is based on the color of a strip; However, the digital tester provides an accurate reading, so no guessing is needed. In addition, using enough test strips will increase your costs in the long run. Multifunctional salinity tester: The ORAPXI 5 in 1 tester can measure salinity/pH/TDS/EC and temperature level, suitable for most spas and saltwater spas. Easy to use: all you need, you just need to immerse the tester in your swimming