Citrisil and Citrisil Blue tablets continuously disinfect and maintain dental water lines. Simply start with one Citrisil Shock tablet and follow with one Citrisil (white) or Citrisil Blue tablet per refill of each self-contained water bottle. Using distilled or purified tap water, the tablet effervesces and provides a safe, pH balanced treatment. Citrisil Blue produces a light blue tint for visual compliance. EPA registered to produce less than or equal to 10 CFU per ml HPC purity; 50 times below the ADA and CDC guidelines.