If you are doing 8000gph never worry about o2 unless u are keeping this tank really really hot. don't put media in your overflows you won't be able to clean it and it will get nasty
+1. U will never have to worry bout a aerator/bubbler if your running that much flow. Also u can run a wet/dry sump with trickle system which will also provide lots of oxygen for your tank. I'm not running any aerators. Just 10000gph of flow and a trickle system.
Sent from my iPad using MonsterAquariaNetwork app