Does anyone know anything about gardening?

I was rather surprised when, after a good night's rain just after I'd installed my water butt, it was full in the morning. All 300 litres, full to the brim.

I then decanted the water to another and it filled up again. Now moving the water to a massive one bit by bit as I haven't hooked that one up as I'm deciding whether to try and elevate it.

Sounds like the prepping's going well. How's the bunker?