The 2oz. size is perfect for treating stored water in 55 gallon or smaller drums. It is also ideal for treating water in RV storage tanks, animal drinking troughs, on site water storage tanks such as cisterns or camp water systems. Aquamira Water Treatment treats drinking water using chlorine dioxide to kill bacteria, control the build up of slime and improve the taste of stored water. Our chlorine dioxide formula has consistently proven to be effective in clear, muddy, warm and cold water. The economical 2oz. size boasts the same portability and long shelf life as our popular 1oz. dropper bottles and allows this highly effective treatment method that can be easily carried and used by individuals anywhere in the world. Each kit contains everything you need to treat up to 60 gallons of water.