Bioguard Balance Pak 100 (25lb)Proper total alkalinity prevents pH from "bouncing" due to rain, bather load, and other chemical application. This helps prevent pool staining, plaster etching or liner wrinkling due to improper pH. Product Information: 100% sodium hydrogen carbonate pH 8. 2 For raising total alkalinity Prevents pH change Improves swimmer comfort Prevents corrosion due to improper pH Protects vinyl liners from wrinkling due to improper pH Directions for use: 1. Add