Abstract: An aquatic scrubbing device for attachment to an underwater ferro-magnetic surface incorporates a carriage, at least two independently energizable electromagnets supported by the carriage for rotation about mutually parallel axes, and at least one drive motor for rotating the electromagnets relative to the carriage, whereby alternative energization of the electromagnets and the drive motors will cause a walking motion of the carriage when attached to the ferro-magnetic surface, the device incorporating rotatable scrubbers for removing aquatic growths from that surface.