It's difficult to determine what will or will not crack a tank, although banana, colas and cinnamon seem to be pretty universal. Factors such as vendors using different recipes, how long a liquid is used in the same tank and the tank itself (they aren't all the exact same material or thickness) come into play. Personally, I have used glass almost exclusively for a long time, since my favorite
juice is an
aggressive tank cracker (so described by a vendor when it melted the acrylic caps on one his carto tanks).
Pumpkin Spice, to me sounds like it might have cinnamon or nutmeg in it, but I could well be wrong. Here is an on-going list of juices reported to have cracked tanks.
http://www.e-cigarette-forum.com/fo...ices-flavors-crack-tanks-ce2s-clearos-40.html