Fill a 5 gal bucket about half full. Put a garden hose in the bucket and let it overflow. While it is overflowing, stir the sand with the hose, kicking up all the debris and dust. When the water comes out clear, it's clean. I haven't had cloudiness when cleaning it this way.
When gravel vacing, just wave the vac above the sand and kick up the debris then suck it out.