Earlier quoted context omitted.
That's a good guess, but I'd still like to see the final report if and when it is published and whether or not they manage to find the root cause. Likely the differential made the problem worse to the point that something gave but I suspect that there is a deeper underlying cause that made it sensitive to that difference in temperature to begin with. Either a material flaw, an assembly issue or something else.
I'm basing it off of what this guy is reporting. He seems to have an inside legit view. https://www.zerohedge.com/user/105370
There are some eye witness accounts about corrosion around the base of the tank. One way in which that could have caused this is because corroded metal takes up more space than the original and this could put point stresses on the acrylic. I haven't seen any engineering drawings (I did try to find some but there are only pretty pictures) so I'm not sure how much effect that would have but keeping the base corrosion free would seem to be an absolute requirement regardless of whether or not it would have a disastrous effect like this. So I will have to wait until the investigators have gone all over this, given the amount of money involved there is bound to be a very thorough investigation and after having seen a couple of aircraft accident investigations conclude with entirely different findings than the first 24 hours of speculation I've learned that to be patient usually pays off.