The decanter stops at the high water level in the pool before one cycle,as the starting point.When drainage is required,the control component sends a signal to instruct the power device to operate,and the push rod extends uniformly and moves along the trajectory,causing the collection tank of the decanter to move downwards at the designed speed,completing the equal amount of water decanting.When the water level drops to a low level,the downward limit switch of the push rod sends a signal,causing the motor to reverse and pull the water collection tank up to the preset position,waiting for the completion of the next cycle.