pausto wrote on 10/27/2006 7:41 PM:
...go one size larger
than the outlet of the pump, and friction loss almost disappears.

As noted, it's always good to oversize the plumbing, in
fact, aquarium pump manufactures almost always, when
measuring water flow, use larger sized tubing than the
output of the pump. It is almost always assumed that the
user will be using a larger diameter hose than the output
of the pump.

Wayne Sallee
Wayne's Pets