Our bromine strips include a test for total hardness since warmer water temperatures increase the potential for scale build-up making it particularly important for spa owners to maintain proper hardness levels. Just dip an AquaChek Red strip in your spa (hot tub) or pool for one second and remove it immediately. You get test results in seconds. It couldn’t be easier! To keep your spa at its best, test the water before each use. Test your pool at each end, at least twice a week. It’s also a good idea to write down your results each time you test, so you can track changes over time.