Spa Essentials 32534000 Calcium Hardness Increaser Granules for Spas and Hot Tubs， 12-Ounce<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Increases calcium hardness level in spa water</li><li>Helps prevent corrosion of spa equipment and surfaces</li><li>Easy to use</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31498S1jjXL.jpg" noproxy>