As per the site it's ok, but without a decent traffic you can't earn money from AdSense. So, first try to promote your site and get a regular traffic to earn $$ from AdSense.
Forums are not good for adsense income. You need a lot of traffic to achieve it. Apparently you don't have that much traffic. Try to promote your site first.
Try to drive as much traffic as you can. Without traffic.. its almost impossible to get good money. Moreover write legit posts.. that will certainly help you indexing in search engines.