McGrayel Algatec 10064 Super Algaecide for Green, Yellow and Black Algae, 64-Ounce

Will not interfere with pool water pH, or sanitizer levels and can swim immediately after treatment, Kills rather than starves algae and prevents algae regrowth due to biostatic inhibitors, Kills most algae in 8 to 24 hours; black algae in 7 to 10 days, Salt pool friendly Formula contains no metals, bromides, or quats; Works synergistically with chlorine for fast cleanup, Super-clarifics pool water during cleanup function