Back Up 2, a highly effective, broad spectrum algae preventative which works together with Varitab to prevent algae before it starts. It works to keep pool water clear and free of visible algae. Simply apply an initial dose at the beginning of the season then add the maintenance dose on a weekly basis. Back Up 2 won’t evaporate and works even harder when water temperature rises, making it more helpful when your pool water needs the most algae protection. Back Up 2 has powerful wetting agents that penetrate pool surfaces to get to places where algae starts growing.
MSA II algaecide and Algi Shield are alternative products for algae prevention.