If you keep your ants in a cooler and use cold objects to lower the temperature, remember that the cold objects can create condensation. I used a frozen bucket of ice.
Also keep in mind that some drain plugs are over 1cm above the bottom of the cooler.
So despite opening my drain plug every couple of days, water was able to enter my formicariums before it got high enough to reach the drain. Luckily I exchange the buckets every day, so I check on them when I do it.
I had to pull them out of the cooler to drain the lower tunnels of water, the higher tunnels were still safe. Despite a couple hundred ants between my Lasius and Camponotus formicariums it looks like I only have 2 deaths, one Lasius and one Camponotus.
So my two main colonies are currently on a shelf drying out. It will probably take a few days for them to dry out a bit to the point where there is no condensation, then they need to go back into hibernation.
Now I will lay a small towel on the bottom of the cooler and have a second one rolled into a cylinder on one side. The flat towel will absorb the moisture and transfer it to the rolled up one, and I can easily exchange the rolled up one when it gets damp.
I think next year I am going to get a small fridge or an electric cooler...
