The Poku Saeruo Degonjo have used Gean Vymasa or Ion thrusters for all their low thrust requirements. Typically used for attitude control of vessels, docking maneuvers, and position/attitude control for stations.
These thrusters use xenon gas as their propellant. Each thruster has a small fuel container attached for its operation. The container is connected to the main reservoir of xenon for refilling purposes.