FROG 90-Day Algae Barrier - Dry Formula Algaecide Prevents Black, Green and Yellow Algae for Pools up to 20,000 Gallons - Pool Maintenance & Algae Prevention - 2 PodsBrand: FROG Features: 90 Day Algaecide for Pools: FROG's 90 Day Algae Barrier protects your swimming pool from algae with prefilled Drop n Go pods; dry, concentrated pool chemical formula works proactively to keep your pool water pristine Easy to Use Algae Barrier: Simply drop the algaecide pods in the skimmer, wait 24 hours as they dispense and discard the used pods when you empty the skimmer for an effective algae barrier In Ground & Above Ground