love to see your results once you have it setupI have the SS-60 for a new tank i am sitting up in the next month. Purchased 2 Reef Octopus Vario S-6 pumps for dual return pumps. I was able to dry fit them as long as I pulled the muffler off the front. I have them sideways, each facing opposite direction so the vertical pluming will be offset as well. Plan on screw on or glue some sort of low profile "grill" to keep anything chunk from getting sucked into the pump and damaging them. Haven't set up the system yet, so not running and not sure what issues will encounter. From a space perspective, they fit.