Ive downloaded a few calculators to help with the measurements, but they all have a spot for distilled water. Is it common to use water? Or just certain recipies call for it?
I don't like the way water feels in most of my vapes but some fruits benefit from the crispness it gives it. I use the eJuiceCalculator and it defaults water to zero.
As Jim_MDP said, water can be used to thin a PG-free juice.
It doesn't take much; too much and your vapor will be "steamy."
Use distilled or DI water. Do not use tap water or drinking water.