Hydraulic fracturing fluid is a mixture of water, sand, and additives. Sand and water make up 99.5 percent of the liquid used in the process, while the other .05 percent is comprised of additives which serve a specific purpose in the process, such as reducing friction when the solution is pumped down the wellbore, preventing corrosion in pipe and eliminating bacteria from the water
You can find additional information on why the additives are used here, and a full list of possible additives used here.
