MM wrote:
:: I can't visualise the quantity. Is it a lot? It's 219 UK gallons,
:: but that is still a quantity I can't really get my head around.

Visualise six 40 gallon drums, five of them full to the top and the last one
half full, together they are 1 cubic metre of water.

:: How much would I use watering the garden? 20 minutes with a spray
:: head on a hose over approx 75 square meters, that is.

depending on water pressure etc, approximately 40 gallons, I know this
because today I filled a 40 gallon drum in the greenhouse[1] with the
hosepipe and it took about 20 - 25 mins.



[1]
I always keep a drum of water in the GH so that it warms up on hot days, the
plants in there don't appreciate cold water too much.
--
If God had intended us to drink beer, He would have given us stomachs.