ST-100 Frost-Free Stock Tank Description Heat from the earth and incoming water keep water in the tank from freezing. Some pre-installed requirements must be met (see below), otherwise the unit is ready to install in your corral. Specifications Capacity: 100 gallons (appropriate for about 400 head of cattle Heavy 10 GA Steel Construction Fully Insulated Internal Plumbing Included       The tank above was installed in 1992 and it is still working great! This picture was taken after about 14 years of service.