you wont need an airrator dude. i think its much more important, to just do a bit of a water change when you add a fish to an overcrowded tank... and every so often.
this not only airates the water but more importantly gets some of the polluted water out.
i think pollution from all the burley ya big breambos are coughing up inside the tank becomes a problem way before lack of oxigen does. and by the way kick ass tank man.