Our twin bilge pumps pull water into the system through their own proprietary inlets. This water then flows through reducing couplings, creating a high pressure system in the boat. This water then flows out through the outlets behind the boat. However, to redirect water to our turret we initially had solenoid valves to restrict flow out of the outlet forcing water up to the turret. A solenoid valve there is also released allowing water to shoot from the turret. We realized pretty quickly, however, that the solenoid valve was severely restricting the flow rate in the system even when not actuated.
A solution we came up with was to replace the solenoid valves with pinch valves. When activated, the valve turns a lever which squeezes the tube up against a metal screw. We also found that the third valve to restrict flow out of the turret was unnecessary since there are significant loses which prevent water from flowing out of the turret uncontrolled. In other words, water only pumps through the turret once the pinch valves are actuated.