Larry, why do you say no PG solution and only distilled water? I use xikar cristal humidifier with PG solution - should i change to distilled water?
The Xikar Crystal Humidifier will work just fine with only the use of distilled water.
PG Solution, regardless of the brand name is basically 50% distilled water and 50% polyglycol. It is my understanding the polyglycol does not evaporate, so every time you use it you are changing the chemical balance from 50-50 to 60-40, to 70-30 until you really only have polyglycol in your humidifer.
I've been smoking cigars and storing them in many different types of humidors and cabinets for the last 30 years and have never used anything other than distilled water and it has worked just fine for me.