go to your pharmacist and order a pint for about 10.00 or a quart if you are young and plan on living a long time. their is only one grade of pc as far as i know.
the pg is mixed elually with distilled water. it is not neseccary to mix the entire bottle,just enough to moisten your humidifier, which as you have read by now you should make yourself. as the oaisis feels dry, add a little distilled water only and only as much as the oasis will absorb.
the pg is good for about a year and then you can flush it with distilled water, and recharge it.
here is one of the interesting and more then one really cares about site. be an expert.
http://www.ertco.com/hydrometers.html
if you want an article about the whole humidor thing, i'll be happy to send it to you.
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