I'm a fan of the 3 chamber ('fuge - return - skimmer) model as well.
Just like others have described, I have three 1" drains, one of them goes straight to the refugium, while the other two are merged into a 1 1/2" pipe that goes to the skimmer section. So that's 1/3 water goes to 'fuge, 2/3 goes to skimmer. Return is in the middle with a bubble trap between both sides, 'fuge and skimmer.
Again, 'fuge on the left, skimmer on the right, return in the middle.
You can achieve the same with 'T's if you don't have 3 dedicated lines like I do :-)