SpaGuard Calcium Hardness Increaser | Spa Balancer

SpaGuard Calcium Hardness Increaser raises the calcium hardness level in spa and hot tub water. It's an easy fix for one of the most overlooked balance problems in spa care: water that's too soft. When calcium runs low, the water turns aggressive and starts looking for minerals to dissolve — pulling them out of your equipment and surfaces instead.

Low-calcium water causes three real problems. It corrodes metal components like the heater and fittings, it can etch and damage spa surfaces, and it tends to foam. Maintaining a proper calcium hardness level protects your spa from all three. Calcium is one of the three core balance numbers — alongside pH and total alkalinity — and keeping it in range is part of water that's gentle on both your spa and the people in it.

This granular formula dissolves into the water to bring soft water back up to a protective level, and it works with every common sanitizing system.