The optimum amount of water to titrate to achieve the best precision and utilize the least amount of time and reagents is between 400ug and 4000ug of water.  While it is easy to titrate down to less than 10ppm of water the precision will be best above 400ug.  Above 4000ug does not improve the accuracy and it takes longer to titrate and uses up more of the reagent.  It is best to determine what sample size should be utilized to have the ug of water fall in this range.

ml or grams of sample	ppm	% water	ug water
1.0	400-4000	0.04%-0.4%	400-4000
0.1	4000-40,000	0.4%-4%	400-4000
0.01	40,000-400,000	4%-40%	400-4000