Note that if you have multiple suction or return lines, the flow will be distributed between the lines such that the head loss in each line is equal.
If the lines are the same diameter and length, the flow will be equally distributed.
If the lines are different diameters and/or lengths, the flow will be unequally distributed.
For example, if you have (7) 100 foot long return lines at 3/4", 1", 1.25", 1.5", 2", 2.5" and 3", the flow will be distributed between the lines at about the following:
3/4"........1.5%
1"............2.7%
1.25"......5.4%
1.5"........7.8%
2".........15.4%
2.5"......24.4%
3".........42.8%