Ive used it for years no problems. Just treat it like RO , it usually has very low ppm so add Ca and Mg maybe some silica. This water also has a low alkalinity so any PH adjustments will have a major effect, usually just nutes make it too acidic so an UP of sorts is needed. This is where the silica comes in, I use it as an up instead of nasty chems. I dont understand how any air contaminate would get into the water. If it comes off the HEAT exchanger wont it be pretty much sterilized from the heat.