Sounds like you're on the right path. Is the tank drilled? If not you'll need an hob
overflow as well if you go with a sump. Focus on the sump first. Then get a skimmer rated at minimum the total water volume of tank and sump if not double. Then look at return pumps and overflows. The overflow needs to be rated at more gph
than the pump after headloss or you will need a ball valve between the pump and display tank to throttle it down. Do you plan on having corals? If so you will want to get enough total gph
in the display to be 30x-45x water volume of the display tank. That's where the powerheads come in.