[Witchdoctor]

Agreed ... it does not matter in the laest

what matters is the head ... which it the total height the water has to travel in the system. The lower the less head. This is how pumps are rated ...

so for example you may have a pump that can do 4' of head at 400 GPH but with 3' of head that same pump would be able to do 500 GPH ....

so the lower you can keep it in reference to the pump location the better

tube length also goes into it but is not as much of a factor as head pressure.

there are formulas for head and drag so you can figure out your exact flow rate based on the real world application as well as knowing the specifications of the fittings you use.