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SpaGuard Calcium Hardness Increaser (12 oz) - Hot Tubs, Swimming Pools, Bangor, Ellsworth, Hermon, Maine
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Leisure Pool Calcium Hardness Increaser [Calcium Chloride] - 25 lb Pail - Leisure Pool & Spa Supply, Inc.
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Clorox Pool&Spa 4-lb Calcium Hardness Increaser Pool Balancer in the Pool Balancing Chemicals department at Lowes.com
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