Weightloss can taper to less than half a pound per day as the fast progresses. Quite usual for weightloss to stagnate during a fast as well, and for days at a time, because the metabolic rate is lowered by one quarter to two fifths to conserve food reserves.
If your doing a water-only-fast to lose weight, then I'm afraid this is not the best way.
Much also depends on how much water you are drinking.
If your goal is to lose weight and more quickly and efficiently then this might help...........http://www.drfuhrman.com/weightloss/default.aspx