Earth Science Labs develops innovative water treatment chemicals. The PristineBlue Complete Pool and Spa Care System is effective, affordable & easy. Applied just every 2 weeks, this premium line is only available at authorized dealers, not mass retail. The ESL Specialty Chemicals Line is available through distribution and includes high-performance products such as AlgaeShield and MetalShield. AlgaeShield is a 30-day algaecide for prevention & treatment. MetalShield is a one-step metal stain remover.