McGrayel Algatec Algae Remover Easy Care Super Algaecide-Clarifier 2 Quart P/N: 10064 Algatec Benefits: Easy to use for algae removal and cleanup. Will not interfere with pool water pH, chemistries, or sanitizer levels No wait, swim immediately after treatment. No testing required, does not require chlorine for algae removal. Algatec Features: Fast Effective Algae Removal. Kills and Controls all algae, green, yellow and black. Superior effectiveness and fast results in just 4 to 24 hours - Most Algae. Eradicates difficult Black Algae(fungi) growths 7 to 10 day. Very Effective with or without chlorine. Strongest, fastest acting algaecide available. Metal-free, non-hazardous to. Algatec provides superior cleanup especially in chlorine and salt pools due to its strong killing action with all types of chlorine products. The product is both an algaecide and algastat (prevents re-growth). Algatec also eradicates Black Algae (fungi) with chlorine in just 7 to 10 days. Unlike phosphate remover products that seek to control algae by phosphate starving, Algatec kills algae and prevents its re-growth. This amazing product makes it easy to control algae blooms and leaves pool water sparkling clear.