Retention tank on the property, what opportunities does it offer me?

I have looked at the pictures. I think I should take a look inside the cistern to inspect the piping. How is the whole thing with the frost protection?

Before winter, you just have to drain the water pipe to the point of use. That's it.

Hello,

my concrete cistern is also filled in winter and does not freeze. We also water with this water in winter.
But as wrote: you have to empty the withdrawal line.

I also do that after every water withdrawal.. By unplugging the pump and briefly opening the tap.
It has been working wonderfully for 4 years.