Calcium Hardness Increaser
Calcium hardness increaser raises dissolved calcium to help prevent aggressive water and protect spa surfaces and equipment.
Why this chemical is used
Calcium hardness matters because very soft water can be aggressive, while very hard water can scale.
When it is needed
Use calcium increaser after testing fill water. If calcium is already too high, dilution is often more useful than adding more products.
How to use it safely
- Test before adding anything.
- Calculate dose based on actual spa volume.
- Add chemicals separately with circulation running.
- Wait, circulate, and retest before adding more.
- Follow the product label and spa manufacturer instructions.
Small spas are easy to overdose. When unsure, add less, circulate, and retest.
Recommended spa supplies
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