A method and system for treating feedwater includes evaporating a portion of the feedwater in a first evaporation chamber so as to separate water vapor from the remaining feedwater. In addition to sanitizing the habitat the production of ammonia and odor from fecal matter and urine is inhibited or terminated. The display device is rotatably coupled to the image capture device such that the display device can rotate between a normal position and self-portrait position. The portion of the cabin below the elevated walkway has a ceiling area that is elevated relative to either the deck portion of the bow area or the cockpit area deck portion where the elevated walkway overlaps the cabin space. The second guiding passage serves to enable a short-distance movement of the head slider on the ramp member.