A self contained floor standing unit consisting of a tank with tappings connected to a bank of piezometer tubes. The apparatus is a transparent-sided tank, mounted on a steel-framed bench with worktop. It demonstrates flow through permeable media with common structures such as dams and walls. The tank is clear so students can see the flow patterns. The rear of the tank contains pressure tappings. Each tapping has filters that stop any unwanted particles. The sides are plate glass to resist abrasion from the permeable medium. The tappings connect to a bank of piezometer tubes at the side of the apparatus which allow measurement of the head distribution along the tank. Removable stainless-steel mesh baffles at each end of the tank hold the permeable medium in place. The top of the tank is open to allow students to fill the tank and set up model structures. At each side of the baffles are end compartments with adjustable overflow pipes for setting the water levels at each end of the model.