Normally, you have a main line conduit from the main house breaker panel to the subpanel like an IntelliCenter with 4 wires including 2 hot (Red and Black), 1 neutral (White) and one ground (green).
The wires have to be sized based on the total expected load (Plus any future upgrades), the distance and the voltage drop.
In the subpanel, you have separate GFCI breakers for each pump and a conduit from the subpanel to each pump individually.