Hey Fcat,
Red Sea responded to a question I posed in the "Ask Red Sea" thread a few months ago where I asked about the wood damage I saw. They said flatly the 130/250 stands were not meant to have a sump in them or any other equipment that could spill water, they did not say it was the cause but it was possible. The wood damage I have, in my mind, is do to the spills I've had over the years and and me not getting it cleaned up or dried out as well as I thought I had. I had rubber matting around my sump and up the sides I was confident was directing any spilled water to a catch area. but that was not the case. Water, I think, mainly from skimmer cup overflows and spray was getting down the wall and behind the rubber matting. The stand has no mold, it's salt creep where the water got into the wood.
I've thought about the MP-40s but I've always kept the motor vibrations to the minimun possible and that was checked several times a week every week. Also my MP-40s never ran much more than 50%. I have never read a thread anywhere that an Ecotech pump of any size was the cause of a tank crack.
Searching the web for others with tank glass crack failure on any type of tank seems to come back to an off center/balance stand more times than not if it was not a impact that caused it. To me, this is the stand getting wet and over time added pressure towards the front corner as it shifted to some degree. This was not a Red Sea problem but I also now understand why the S series has a metal stand with their complete sump package under it.
As long as you tear the sump down and check all this out more than once a year (as I did) You probably have nothing to worry about. You can always build a new/better stand and get away from this possibility which was what I was in the process of doing when it failed. As I said before, even if Red Sea had told me this in 2009 instead of 2012 I'd still have added the Sump. Thanks!