i use de-ionised water( alarmingly its the stuff you get for car
batteries from your local garage)
i use it with pure vg mixes ( im still tryin got work a good recipe as of yet)
from what ive gathered its simply for thinning generally 85/15% combination due to pure vg being very thick. the reason for using the de-ionised is simply because it is purifed and has none of the chemicals that are found in standard tap water that tend not to make for a very nice mix. when you prepurchase vg it is premixed with either de-ionised or alcohol to thin the mixture down. but you can
buy a 1ltr bottle of the stuff for less than a £1 in the uk , undoubtably less for usa.
this is what ive gathered so far from asking the same question
