Leslie's - Hardness Plus for Calcium Hardness, 4 lbs.
$19.99
Keep your calcium hardness at proper levels at all times to help protect your pool, water, and pool equipment with Leslie's Hardness Plus, 4 lbs.
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Keep your calcium hardness at proper levels at all times to help protect your pool, water, and pool equipment with Leslie's Hardness Plus, 4 lbs.
- 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.
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California Residents WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
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. In addition, Calcium Hardness often goes hand in hand with other aspects of pool water chemistry, such as Total Alkalinity or pH.
- 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.
| Container Size: | Bucket: 4 lb |
| Chemical Type: | Calcium Hardness |
| Dosage: | 1.25 lbs per 10,000 gallons |
| Manufacturer: | Leslie's |
| Product Type: | Pool Chemical |
| Equivalent SKU: | 18778 |
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.