wrote:

In alt.solar.thermal daestrom wrote:

I was thinking of a helical arrangement, you're talking about a spiral like
a phonograph groove.

What do you do when you get to the center of the phonograph?
Isn't there still at least one crossover needed?

Greywater might enter and leave via the upper vertical arm of a 4" PVC T
at each end of the corrugated drainpipe spiral. Fresh water might enter
and leave via the ends of the Ts.

Nick