I've used Xtol for the past several yeas and am quite happy with it. I recently realized the instructions read specifically to mix it using distilled water. I have a water filtration system for my darkroom, but I realize it is not the same thing as distilled.

Keep in mind, that I live in Portland, Oregon where our water source is mostly from treated rain water and does not have fluoride added. It is considered very soft, as in few minerals.

I have never noticed any ill affects form using my filtered water. So I'm wondering, is it worth the extra effort / expense to switch to distilled for mixing my Xtol?