Peter, lol, I just typed a long response and comp froze, ugh...this is abbreviated, for now...
initially the of was going to be "usable" space, it is about 40 gallons, a nice tank but I wanted lots of flow in of and in tank, and wanted a totally unobstructed view and free from powerheads and wavemakers...
so, the overflow drops into the leftside fuge and is returned to the tank via the dart thru eight, 8inch long loclines...
the tank empties into the rightside fuge and is returned to the tank via the hybrid and two 3/4 inch pipes...
the fuges are connected...
the bluline that runs the skimmer can be redirected to the 8 loclines for an extra blast...
plan now is to add a 4 arm locline hat to a return (possibly both?) to get a bit more flow in the lower part of the tank at that end...