SpaBoss Cal-Rise is completely soluble in water and easily raises the calcium hardness level in your hot tub a capful at a time. Testing your spa or hot tub water regularly will help you keep an eye on this very important part of healthy, clean water. Your hot tub can be damaged with corroded metal surfaces such as pipes, filters, screws, lights, and other hot tub hardware that is in contact with water that has a calcium hardness level below the recommended range. Increasing calcium hardness when it drops too low is critical to a working hot tub that is always ready for you to use.
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