Say you wanted to make a 8oz solution consisting of 93-94% distilled water, 3% 1,3-propanediol, 3% sodium lactate (powder)
1) Would Germall Plus (powder) be an adequate preservative here, or would another work better (I read it might not work in sprayers)? If so, do you always use the minimal recommended percentage?
2) Do you have to heat and hold?
Also, seeing as the humectants add up to 6%...is that a good amount...what's the max recommended amount (before the solution would become irritating, if possible)?