When supplying a jet siphon during a dump site operation, the key is to set a pump discharge pressure so that a good, solid stream of water can be seen coming out of the water transfer tube (hard suction). Pressure requirements can vary - but visualizing the discharge stream almost always works best - that and a pressure of around 125 psi. For more definitive test data and recommendations - take a look at our jet siphon flow test study in the Data Section of the Big Water Information Tab
Jet siphon flows are critical during multiple dump tank operations. You have to be able to transfer water at the same rate that it is being used at the fire.
