📌 What It’s For:
Raises calcium hardness in spa water to prevent corrosion of equipment, etching of surfaces, and foaming caused by soft water.
✅ How to Use It:
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Dose: 1 tablespoon (0.5 oz) per 100 gallons raises hardness by ~25 ppm
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Apply by: Broadcasting evenly over the surface with circulation running
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Wait Time: 4 hours before retesting and rebalancing if needed
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Frequency: As needed, especially after draining and refilling
⚠️ Safety Notes:
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Avoid exceeding 400 ppm to prevent scaling
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Always test water before adjusting — only raise if below recommended range
💬 Pro Tip:
Essential after a fresh fill or when using softened water. Balanced calcium helps maintain clear water, extend equipment life, and reduce chemical demand.