What causes the tanks to break exactly? Is it a chemical reaction of some sort? I must admit I would be sceptical about inhaling something that breaks plastic...
My understanding is that it is a chemical reaction upon the plastic "polycarbonate" with certain flavors, many of which fall into the cinnamon or citrus flavors. Certain molecules in the plastic bond with certain components of the juice; as more and and more molecules break their bonds with the plastic and bond with the juice molecules, the plastic's mechanical structure disintergates by cracking or melting. This is why you can often see "strings" in the juice attached to the cracks in the walls of the tank.
If it isn't already obvious, don't vape that juice any longer. Consider it contaminated with the leached chemicals in the juice.
I've written about this phenomenon for my blog. I have a video demonstration of a tank melting. The above list of flavors known to crack tanks. And I've provided photo examples of juice delivery devices that are safe to use with these juices. Just find the title, "Something Safe or Cinnamon and Citrus Flavors" and then click the title to view.
E-Cigarette Forum - Baditude - Blogs
My favorite flavors have grown to be among my favorite flavors. One vender happens to be my favorite and specializes in fruit flavors. The name is
Dripeez. My favorite is the Golden Apple, that gives you the taste and scent of biting into a Golden Delicious. It's also great with some Cinnamon or Rum flavor added. I also give high marks to the Pear, Lemon & Lime, Orange, Kiwi, Watermelon, and Cinnamon. All of these juices are all-natural, all-organic flavoring. Your choice of pg/vg ratio.
https://natural-eliquid.com/store/index.php
I use only pyrex cartotanks, the majority being IBTanks, so that I have no concern about what flavor I decide to use or try.