My toilet uses a 4-litre high-level cistern. Being a high-level cistern it
gives a more efficient flush with less water.
Rainwater collection tank
Rainwater collection tank
Feed to toilet cistern
The cistern is fed from a tank that collects rainwater, so it uses no
mains water at all. The feed does have a bypass valve to use mains water
if there is no rainwater available. I have only occasionally had to fill
it manually. I am intending to modify it to automatically top up when
almost empty.
