"Graham Harrison" wrote in message
...
Continuing from the previous thread, I think I'll have to replace at least
one of the toilet. Since I have a septic tank the idea of reducing the
amount of water used seems sensible.

Why ? Septic tanks rely on a reasonable amount of water flow. Also they
are often installed on quite a low gradient and so you need all the water
you can get to move the other stuff to where it belongs.