I'm running a (used, but new to me)180Gal. with a sump. I have a FX5 being delivered Friday, from California. I currently have 6 RBP, and a few Large Pleco's. (12 Inches) in the tank. My question is, when I bought the tank it was up and running, but the return line was only hanging off the back of tank, about 3 inches under water. This was the only filtration and water flow for the entire tank( There were 30 fish in there). When I hook the FX5 up this weekend, what is the best way to position the Lines (in and out) to maximize the FX5? Should I pipe the Sump return to bottom of tank to keep a steady flow over the gravel? This is my largest set-up for me so far, and I'm a 1st time sump, cannister user. Any info would be appreciated.