Make sure the lids are tight fitting. Even the smallest extra hole in the little plastic back strip on the lid can be an escape hole. And weighing down the top is a good idea.
I had a wonderful wild caught Koliba lap. and it managed to pop open the top of the 75g QT tank and die. That 75g did have pretty thin glass and was not as much effort to get out. So weigh down the lid too!
This was the one I lost. What is so special about this on was that this coloration was while it was still in QT! This was like day 2 of having it. Nice olive green with tall finlets made for a good looking koliba lap.
It came in on a Friday and had jumped that weekend on Sunday night. $185 down the toilet!