Applied Biochemists HCL Advantage Acid Wash 1 Quart P/N: 406603A HCL Advantage is an additive for muriatic acid when acid washing pools. Adding HCL Advantage to a solution of muriatic acid and water will thicken the washing solution. The new solution adheres to pool walls longer making cleaning easier and safer. Features: Makes Muriatic Acid Work Better Reduces Acid Fumes Thickens Acid Solution for Safer, More Effective Cleanin Added Sequestering Agent Prevents Bottom & Drain Staining Applications: Normal: 1. Mix muriatic acid with water at the recommended rate of 1 part acid to 4 parts water. Increase strength or use straight acid for tougher stains. 2. Add 1/2 pint (8 FL OZ.) of HCL Advantage for every 2-1/2 gallons of acid wash solution.