Even with the best chlorinating program, you will need to protect your pool against algae growth. BARACUDA® Pool Algaecide is a good option for regular protective treatment. If you already have algae in your pool, BARACUDA® Algae Killer is a good solution. It also can be used as a protective treatment in peak, hot season. If your pool has blackspot algae, then Blackspot Killer is more appropriate.