Apparatus for remote inspection of fluid containers, e.g., portable tanks, includes an electronic circuit in communication between each container (or at various locations along a pipeline) and a remote central station. The electronic circuit is adapted to issue a signal to the remote central station that includes information about predetermined internal and/or external conditions such as the level of liquid stored in the tank, a pressure condition of material stored in the tank, a lack of presence of the tank in an installed position, or the presence of an obstruction restricting access to the tank.