Abstract: Embodiments of a water bottle cap system that is backwards compatible with existing water bottles and methods of its use are described herein. According to one exemplary embodiment, a water bottle cap system includes an at least three gallon water bottle having a pouring neck extending from a water bottle body and a water passage penetrating pouring end of the pouring neck opposite the water bottle body. The system also includes a tear-away resilient sealing cap having a sealing end matingly mounted to the pouring neck and a cylindrical section extending from the sealing end and having a pouring-neck-surrounding portion surrounding the pouring neck intermediate the water passage end and the water bottle body.