From the manufacturer

Aquatabs is a purifying tablet which is added to drinking water to kill harmful micro-organisms. The tablet quickly dissolves and disinfects water in 30 minutes. Each tablet can treat up to 64 ounces of water.

Specifications

• Each tablet treats up to 64 ounces of suspect water.
• Effective against giardia cysts, bacteria & viruses.
• Just mix thoroughly for 10 minutes and allow to stand for 30 minutes before drinking.