9.6Our score 4 photosBoost Water Quality: Prevent cloudy, dull water by restoring the right calcium levels in your pool
Ranked #99 in Garden & Patio · 4 things we like
Quick answer The In The Swim Calcium Hardness Increaser scores 9.6/10 with us. Amazon owners rate it 4.8 out of 5 across 1,246 reviews, above the 4.6 average of the 16 pool balancers we track. It was listed from $59.99 to $86.99 on Amazon depending on the option when we last checked in September 2026.
Boost Water Quality: Prevent cloudy, dull water by restoring the right calcium levels in your pool Protect Your Pool: Helps stop costly damage like corrosion and pitting on pool surfaces and equipment Easy-to-Use Granules: Fast-dissolving formula works quickly—just measure, pour, and circulate Dial in the Perfect Balance: Raise hardness 50 ppm per 6 lbs per 10,000 gallons—easy, accurate, and powerful Multi-Use Chemical: Highly effective for swimming pools—and also serves as an industrial-grade ice and snow melt
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| Brand Name | In The Swim |
|---|---|
| Package Size Name | 25 Pound |
| Number of Items | 1 |
| Unit Count | 400 Ounce |
| Item Highlight | Fast-Acting, Scale Prevention - 94% Calcium Chloride |
| Model Number | Y7210 |
|---|---|
| Item Form | Granular |
| Product Benefits | Prevents Corrosion |
| Item Weight | 27.6 pounds |
Yes, it is one of the stronger picks in its group. We score the In The Swim Calcium Hardness Increaser 9.6 out of 10. Amazon owners rate it 4.8 out of 5 across 1,246 reviews, above the 4.6 average of the 16 pool balancers we track.
It was listed from $59.99 to $86.99 on Amazon depending on the option when we last checked in September 2026. That is more than the $23.05 median for pool balancers in our catalog. Amazon prices change daily, so use the price button on this page to see the current figure.
Amazon lists 2 options. Style: Bucket. Size: 25 Pound, 45 Pound. Pick an option on this page and the button opens exactly that model.
Similar, well-rated pool balancers in our catalog: Pool Mate 8-Pounds Premium Calcium Hardness (9.4/10, 4.7 stars from 1,384 owners); Pool Mate 10-Pounds Premium Alkalinity Increaser (9.4/10, 4.7 stars from 1,282 owners); Pool Mate 10-Pounds Premium pH Up (9.4/10, 4.7 stars from 2,693 owners).
Pool Mate 8-Pounds Premium Calcium HardnessPool Mate 10-Pounds Premium Alkalinity IncreaserPool Mate 10-Pounds Premium pH Up
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