Pristine Extra 4lb.
Pristine Extra® contains 99% sodium di-chlor (granular chlorine). It is an effective shock treatment that can be used at start-up, routine maintenance or for troubleshooting as needed. It is a primary sanitizer.
Just follow the maintenance program every 2 weeks.
Pristine Blue® is EPA registered in all 50 states, is NSF 60 Certified and gentle on equipment. It is compatible with most systems including salt and chlorine. Pristine Blue® is safe to use on all pool and spa surfaces.