An improved apparatus and method for monitoring the levels of propane or other consumable liquid in remotely located storage tanks and coordinating delivery of liquid to those tanks, including an improved method of using the remote monitoring data to identify out-of-ordinary conditions at remote tanks, optimally schedule purchases or deliveries, improve safety, and more efficiently operate a propane dealership. More accurate and timely information concerning the status of customer tanks serves to improve operational efficiencies and increase safety. Data received from remote sensors can be collected and organized so that it is easily understood and utilized through the implementation of a user interface accessible via the Internet that allows the information to be presented in an efficient graphical and contextual fashion. Operational efficiencies can also be improved by calculating site-specific Degree-days and K-factors for each tank and by taking historical propane usage for each tank, weather conditions, and projected fuel usage into account.