Here's the scenario, im planning to set up a 72 inches by 30 inches by 24 inches (approximately 218 gal) main tank with a sump 65 inches x 20 inches x 18 inches ( its about 100 gal approximately). Im going to have a drilled tank on the side i just can't figure out how big should be my outflow? will 1.5" outflow be enough?or it is better if i install 2 outflow? this will be my first big tank i need to get it right. Your input will be appreciated. Thanks!