im running a 100 gal and a 60 gal with 1 sump also. the set up is from this idea but instead having 2 tank next to each other, i have the 100 galon on top, 60 on the left bottom and the sump 40 gallon in the right bottom right next to the 60 gals. the pump will pump water to the 100 gallon----> ( use overflow) to get water to the 60 gallons(right at the bottom of the 100galon)----->(again use overflow) to get water to the sump and keep going circle. 100gal -> 60 gals--> sump. it's very simialr to your diagram but just having 1 top and 1 bot with sump next to the bot tank. ^_^