If you want to use your sump as a fuge the flow has to be much less then what you want your display tanks turnover which is around 10x. so maybe you will have to just use a sump for your skimmer,heater and pump?
This is why I suggested a wet/dry you could DIY one maybee

check this link out. for the gen x pump I would recoment the GX8500
Aquarium lighting, aquarium filters, protein skimmers, aquarium pumps, aquarium products
GX8500
Gen-X submersible pump
2249 GPH
16.4ft maximum lift
UL approved
Ceramic shaft, adjustable flow. 33' cord
1 year guarantee against manufacturer defects.
3/4", 1", 1/14" ID Hose fittings included.
Power Consumption 230 Watts
1900 GPH at 3" Head.
1750 GPH at 5' Head this will decrease a bit when you put your 90degrees fittings for the return to tank.
PSI rating 7.82