After removing the test tubes from the fridge, water from behind the bung leaked into the chambers and drown ~1/3 of my queens. Is there a trick I don't know to prevent this or does this happen occasionally? I wonder if the change in temp caused condensation? Maybe the warmer water expanded and under pressure squeezed through the bung?
I probably needed to pay better attention, I took them out and left them for about a week assuming they would slowly wake and would be fine 'til then. There were only a couple with workers (most were Lasius and Crematogaster caught in September).