It’s cold.

There’s about 2″ of ice on the pond. It’s barely even frozen before.

The level’s dropped so I switch on the hose from the water butt. Not much happens… the water’s frozen there too, so it’s probably frozen in the pipe. Eventually a trickle comes through and grows until I can top the pond up properly. The ice on top of the water butt stays where it is as a vacuum forms beneath it…

A few hours later I can still see the thick ice, unmelted, sandwiched between the water above and below. I can see the fish swimming below the ice, and a probably rather confused frog has come in and is swimming across the surface water above the ice. It’s finding it can’t dive, I don’t know if it understands why…