flow for closed loop

[FragIt Dan]

Originally Posted by The Grizz

Actually now that I think of it, it's really a 1-1 ratio related to water volume in & out. I might be totally off here because of an 19 hr day yesterday.

Flow is relative to cross sectional area, so for 2" pipe it is 3.14x1^2= 3.14 vs 1" at 3.14x0.5^2=0.79, but two of them so 1.58. That puts it at 2:1. You would need four 1" return lines to prevent a bottle neck.