Aquachek 4 Way Chlorine Test Strips 50 Pack Hot Tub Swimming Pool PH Strip Dip

Total Alkalinity - keeping this correct will stop sudden PH changes. Stabilizer (Cyanuric Acid) - An ideal level of Cyanuric acid protects against chlorine loss caused by sunlight. Keep PH between 7.2 and 7.6 on the scale.

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