Keep you spa water in top shape and properly balanced with a new test kitt Test kits are extremely important in maintaining proper levels of your spa or hot tub. These test kits will measure all of your water's vital chemistry levels, such as chlorine, bromine, pH, total alkalinity, calcium hardness, and even your cyanuric acid (stabilizer). Knowing what these levels are will allow you to keep maintaining fresh and comfortable spa or hot tub water all season long.