Ok so I mount it with the 3 hole side facing downwards. Green arrow is the single hole on the top for return to res, red arrow goes to pump, blue arrow for drain line, gray cross I just close off.
The thing I don't get is that clear tube inside, why would that be used for return to the res? It looks like i'm meant to keep the water level bellow the top of it, so it's some kind of 'air trap'. If it's just meant to help direct flow from the return back to the bottom of the res faster, then i'd have to put it on the top single hole right? Having a drain line at the top of the res would be silly I think so i'd prefer the 3 hole side at the bottom.
The top single hole lacks the thread on the inside to let me screw in that clear tube actually. It's threaded differently from the bottom three holes.Edited by ilikebeer - 11/7/12 at 11:16pm