I would think that amount of water doesn't matter as much as pH and the napatha I would scale proportionate to the amount of water. So if you used 100mL of water and 50mL of napatha and it worked I would use that as a guideline. You can always do more pulls.
Maybe someone else could advise you better than me though.
"Whereas modern cynicism brought despair about the ability of the human species to realize laudable ideals, postmodern cynicism doesn't —not because it's optimistic, but because it can't take ideals seriously in the first place. The prevailing attitude is Absurdism. A postmodern magazine may be irreverent, but not bitterly irreverent, for it's not purposefully irreverent; its aim is indiscriminate, because everyone is equally ridiculous. And anyway, there's no moral basis for passing judgment. Just sit back and enjoy the show. " - Robert Wright
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