My questions concerns the starting point for calculating the height that water will be lifted by a certain air pressure. It concerns the operation of a "trompe" in the configuration of a "pulser pump". Lets say the height of the water in the downflow column is 100 feet. From there is runs horizontally to an air collection chamber, and from there is runs to the system outlet. The outlet leads to a reservoir at an elevation far enough below the reservoir that feeds the inlet, at the top of the downflow pipe, to create a fast enough flow to bring the air down with the water to the compression chamber.That air collected in that chamber would be pressurized to to roughly 43.2 psi since one foot of water head creates .43197 psi. Now, instead of a line that draws off compressed air , from this chamber, there is simply a pipe which projects down into the airpocket and down into the water. The operation of the pulser pump is thus- the chamber fills with air to the point that water is pushed below the end of the pipe and the air then enters the pipe. The water level will then rise and it will again be above the end of the pipe. Water then enters the pipe. The air pocket in the compression chamber will then increase again and the series of events repeats. My question is this, when the air in the chamber is above the end of the pipe, the water pressure will fill this pipe ( the one in the center of the configuration-not the outlet pipe) to the same elevation as the water entering the downflow pipe. Therefore, when 43 psi of pressure is introduced into the pipe, can it then lift water close to 100 ft above the elevation of the inlet. I'm really asking, do we calculate the height of the water to be lifted form the bottom or the top of the system.