Pentair's Pool and Spa Stop Leak will repair minor water leaks in swimming pools, spas, hot tubs, fountains, waterfalls and any other bodies of circulating water. Stop Leak is used by many field service technicians when a plumbing repair is minor and inaccessible.
Stop Leak can be effective when used in accordance with the instructions. It may be necessary to use Pool and Spa Stop Leak more than once depending on the size of the leak involved. For larger pools, it may be necessary to add more than one quart.
Active Ingredients of Stop Leak: Sodium Silicate.
California Residents WARNING: Cancer and Reproductive Harm
 www.P65Warnings.ca.gov