The present invention is directed to a sprinkler apparatus and related methods for the distribution of fluid. The invention preferably includes a nozzle rotatably driven by a pressurized flow of fluid along a fluid path. The invention preferably includes a housing separating a magnetic drag coupling assembly from the fluid path. The coupling assembly preferably includes spaced apart magnets configured to exert an attractive force on each other to rotate one magnet in response to the rotation of the other magnet, and a resistive/drag force to oppose the continuous rotation of the nozzle. Pressure offsetting structures minimize or even neutralize the upward/downward forces that the flowing fluid otherwise would exert on the rotating shaft assembly.