QUICK DISSOLVING CHLORINE TABLETS: Will fully dissolve and circulate within your pool/hot tub water within minutesMinimal impact on pH levels. So you can use the tablets without worrying about any adverse effects on the water pH levelsEACH TABLET RAISES CHLORINE BY 1.2MG/L(PPM) PER 1000L For best results pre dissolve this product in a separate container of warm water before adding to your pool or spa.