Hot Tub Things® Calcium Increaser – 32 oz Spa Hardness Booster

Hot Tub Things® Calcium Increaser – 32 oz Spa Hardness Booster

Name: Hot Tub Things® Calcium Increaser – 32 oz Spa Hardness Booster
Brand: Phoenix®
SKU: 30209
Price: 25.50 USD
Availability: InStock

Type: Clarifier

SKU: 30209

$25.50

$25.50 ~~$0.00~~

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Hot Tub Things® Calcium Increaser (32 oz) is a liquid formula designed to elevate calcium hardness in spa water to the ideal 80–200 ppm range. Proper calcium balance protects jets, heaters, and spa surfaces from corrosion and improves sanitizer performance. Easy to dose—just pour in with pump running and test over time. Compatible with chlorine, bromine, salt, and mineral systems, this trusted formula ensures healthier water and longevity for your spa.

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Product Description

Precision liquid formula raises spa water calcium hardness efficiently, helping prevent corrosive “hungry” water that can damage heaters, plumbing, and metallic parts.
Ideal for weekly use or fresh fills in spas with low or softened water, restoring balance without overshooting to scale-forming levels.
Helps minimize foam, cloudiness, and sanitizer demand by maintaining stable hardness—essential for optimal sanitizer effectiveness.
Compatible with all hot tub sanitizer types—including chlorine, bromine, saltwater, and mineral systems—simplifying your chemical routine.
Convenient 32 oz bottle with marked dosing lines makes it easy to add precise amounts based on spa volume.
Backed by Hot Tub Things’ quality assurance, safety-tested for spa use and formulated without harsh fillers—trusted by professionals and DIYers.

Specifications

Brand : Hot Tub Things™

Dimensions: 8.74 x 4.88 x 4.09 in

Barcode: 850511004222

FAQ

Q: Why should I add calcium to my spa?

A: Low calcium can cause corrosive water that damages spa heaters, jets, and metal fittings.

Q: How often should I use it?

A: At startup and whenever calcium tests below 80 ppm, typically weekly or monthly.

Q: Is it compatible with salt systems?

A: Yes, safe for chlorine, bromine, salt, mineral, and biguanide sanitizers.

Q: Will it cause scaling?

A: Not when used correctly—keep calcium under 200 ppm to avoid scale.

Q: How do I measure dosage?A: Bottle has clear ounce marks; 1 oz/500 gal ≈ +10 ppm.

Directions

Test current calcium hardness; ideal range is 80–200 ppm.

Pump running, pour 1 fl oz per 500 gallons to raise by ~10 ppm.

Wait 2 hours and retest; repeat if needed at half-dose.

Add weekly or after draining to maintain balance.

Compatability