Just in case anyone is still monitoring this post, we've been advised
by the experts now, and it is feasible, with a lot of money involved,
to attach to the house system.

Having said that, the amount involved to make it potable is prohibitive
for now, perhaps down the track we will consider that option.

For now we are looking at meshing the top securely to stop insects and
such, decking over the top, and using the water for irrigation, laundry
and toilet flushing.
This will save a lot of wastage on it's own.

If you want to know how that goes, email me and I will pass along what
the effects are in future.
Wayne