Aha. In that case, I'd strongly advise more than one ad per page. 2-3 is good. If you can, run 'em through Google Adsense: I don't know what you're using at t

Aha. In that case, I'd strongly advise more than one ad per page. 2-3 is good. If you can, run 'em through Google Adsense: I don't know what you're using at the moment but Adsense has consistently been the highest performer for me, CPM-wise, short of running my own direct-sold ads. And do test different layouts. I've found that changing ad layout on a page can literally be a 10x multiplier on ad income.