Calcium Hardness Increaser For Pools
Calcium Hardness Increaser For Pools
Fast-Dissolving Calcium Chloride for Pools
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Fast-dissolving calcium chloride that restores proper hardness in minutes. Keeps pool surfaces and equipment protected.

Directions for Use
- Add this product directly to the water with the circulation system running and brush any settled product.
- Do not add this product on the same day as another product used to increase pH or alkalinity.
- Add 1.2 lbs per 10,000 gallons of water to increase calcium hardness by 10 ppm (1 lb = 2.75 cups).
- Wait two hours and retest calcium hardness.
Do not dissolve this product before use or mix it with
other products in the same bottle or pail. See label for detailed instructions.

Q: Why do I need to increase calcium hardness?
A: Low calcium levels can cause your water to become aggressive, leading to damage to pool surfaces, liners, and equipment.
Q: What’s the recommended calcium range?
A: 200–400 ppm is ideal for most pool types. Always test before adding and adjust gradually.
Q: Is it safe for saltwater pools?
A: Yes! It’s compatible with saltwater, chlorine, and bromine systems.
Q: How fast does it dissolve?
A: Typically within minutes—just add it directly to the pool with the pump running and brush if needed.
Q: Can I swim right after using it?
A: Yes, your pool is generally swim-ready 15 minutes after the product has fully dissolved.
Q: Is this product compatible with Baquacil?
A: Yes, this calcium hardness increaser works well with Baquacil, helping to protect spa surfaces without impacting your sanitizer.

The price you see is the price you pay.
We don’t play pricing games.
That’s why all orders over $75 ship free—no tricks, no hidden costs.
Why is AquaDoc the Best in Pool Chemicals?
- 🌿 Paraben free & Aluminum free
- 📦 Fast Shipping
- 🇺🇸 Made in the USA
Order With Confidence
If our products don't solve your (pool or spa-related) headaches, contact us for a 100% refund. Free shipping on all orders over $75!
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100% Paraben Free
Say goodbye to parabens that can potentially be harmful to your family. All of AquaDoc's chemicals are paraben and aluminum free.
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