With this amount of traffic you could earn at least $300 - $500 per month, depending on how many pageviews you are getting. In short, $300 for 3 months with this traffic is not good. Try to improve number of pages each visitors visits and tweak ad colors, blending etc to increase CTR. Also, filtering MFAs might help as well. $5 - $10 eCPM is what you should be satisfied at. If your niche is not extremely low or extremely high paying (unlikely ) lolz, he is already making $3 a day. Tell us you meant $10 a day.