Each flush of a toilet uses the same amount of water.
Flushing a toilet uses the water contained in the toilet tank.
to use less water when flushing
No
It will be exaclty the same, the only difference is that flushing the toilet with bottled water is very expense. It really will be a waste of money.
Flushing a toilet
I reckon there is no air vent pipe on the drain line of the toilet you are flushing and the siphon action is sucking out the water in the loft toilet also.
The first flushing toilet was for queen Victoria the first.
The flushing toilet was invented by John Harrington in 1596.
1.6 - 3.5 gpf
That is a matter of debate. Lets say you choose to have untreated water with harmful bacteria including the causes of typhoid and chlolera pumped into your toilet so you will not be wasteful. Then your toddler plays with the water in the toilet and gets sick and dies. I choose to be "wasteful".
It helps to keep your body flushing toxins out of your system, by making you use the toilet more.
The wax ring is just to seal the toilet to the drain. It has no effect on the flushing.
Low water pressure or cold water main undersized.