SpaGuard® Rapid-Dissolve Chlorinating Tabs are premium spa sanitizer tablets formulated specifically for hot tubs, not repurposed pool chlorine. Unlike traditional slow-dissolving pool chlorine tablets, which are sized for much larger water volumes, these tabs are built to dissolve quickly in a spa's smaller volume and higher water temperature. The tablets combine a dichlor-based chlorine sanitizer with a built-in clarifying agent, so each dose sanitizes and helps keep water clear at the same time. Use 1 tablet per 600 gallons weekly to maintain a free chlorine residual of 3–5 ppm. This 1.25 lb container is intended for chlorine-sanitized spas specifically, rather than as a general-purpose additive for other sanitizer types. Store tablets sealed in a cool, dry place away from other chemicals. As with any chlorine-based product, always add tablets to water rather than the reverse, and allow the tablet to fully dissolve before spa use.