I always think that a sump so one can run a protein skimmer and something like an algae turf scrubber is best. You don't have to drill a tank to accomplish this, as a HOB overflow can accomplish this for you...where I'm a fan of the CPR overflow due to this brand having a 'nipple' where you can hook a pump up to suck air out of the "U" bend in it and prevent siphon loss.