Starting over, uuugh!

Been awhile since I posted. Wife called me the other night at work and informed me our 110g acrylic tank was leaking from a lower seam. I had it set up as a FOWLR tank for about the last 2 years with plans on going full reef in the future. Anyway, long story short, I had to drain the tank completely so now starting from square one. All of my live rock/sand is currently in rubbermaid tubs with the tank water, hopefully it will not completely die. The creatures are taken care of. I've fixed the leak and had previously acquired another 100g acrylic which is beat up but usable as a sump, I plan on placing a 10 gallon tank inside this "new" sump for the fuge. I've installed a coast to coast skimmer for drainage in the main tank and would like to incorporate a closed loop system for better flow. The main tank is not drilled except for the 2 holes for the coast to coast, those are 2 1/2". I'm looking for info from the more experienced/succesful reefers for input on how they would proceed if presented with this same opportunity. For pumps I have a Mag 9.5, a GenX PCX 40 (1190 gph) and an Iwaki MD70RLT ( 1500gph).