Leslie's - Hardness Plus for Calcium Hardness
Starting at
$27.99
Keep your calcium hardness at proper levels at all times to help protect your pool, water, and pool equipment.
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Keep your calcium hardness at proper levels at all times to help protect your pool, water, and pool equipment.
- Calcium hardness increaser
- Keeps your pool and equipment free from damage
- Increases Calcium Hardness by 10 ppm per 1-1/4 lbs. in 10,000 gallons of water.
The calcium hardness level in a pool does not increase rapidly, but it is good practice to check the calcium hardness every month. Adding 1.25 pounds of hardness plus to 10,000 gallons of water will raise the calcium hardness by 10 ppm. **The minimum level of Calcium Hardness is 150 ppm.
Signs of Low Calcium Hardness in Your Pool
- Metal Corrosion: When calcium levels are too low, the corrosive nature of soft water can cause it to go after the metals in your pool, including handrails, ladders and equipment.
- Concrete and Plaster Corrosion: As pool water becomes more corrosive, it attempts to balance itself by leaching calcium from plaster, concrete, grout, tiling, or other pool surfaces. This causes pitting and delaminating, which essentially means the corrosive pool water eats away at the structure of your pool.
- Foamy Water: Soft water increases the likelihood of issues with unsightly pool water foam.
AccuBlue In-Store Water Testing
Water testing and pool chemicals go hand in hand when balancing pool water. Leslie's makes it easy with in-store water testing that offers precise water testing and customized treatment plans. Take the guesswork out of balancing your pool water and stop by your local Leslie's pool store for a FREE AccuBlue Water Test, keeping your pool clean, safe, and beautiful. Find your closest Leslie's Pool Store today and stop by for your free pool water test!
AccuBlue Home Digital Pool Water Testing
Looking for an at-home digital water tester? Leslie's AccuBlue Home is the total solution for a healthy swimming pool. It all starts with the testing device, which employs Leslie's state-of-the-art water testing technology to give you comprehensive water chemistry results and recommendations in 60 seconds -- all from the comfort of your own home. It's the only at-home pool water test that precisely measures 10 aspects of water chemistry. Learn more: Leslie's AccuBlue Home.
| Manufacturer: | Leslie's |
| Product Type: | Pool Chemical |
| Chemical Type: | Calcium Hardness |
| Dosage: | 1.25 lbs per 10,000 gallons |
Common Questions:
What is Leslie's Hardness Plus made of?- It’s made of Calcium Chloride, a fast-acting compound that increases calcium hardness in pool water to prevent corrosion and structural damage.
- Add 1.25 lbs per 10,000 gallons of water to raise calcium hardness by 10 ppm. Always test your water first to determine how much you need.
- The recommended range is 200–400 ppm, with a minimum of 150 ppm. Staying within this range helps prevent damage to pool surfaces and equipment.
Low calcium hardness can lead to:
- Metal corrosion (handrails, ladders, equipment)
- Etching and pitting of plaster, concrete, and tile
- Foamy water and chemical imbalance
- It’s best to check calcium hardness monthly, as levels don’t fluctuate rapidly but are crucial for long-term pool health and water balance.