Adsense ads getting stale

[Auction_Mum]

I got great click through rates when I first added adsense to my site but they have really dropped because the ads don't seem to change much. I have a lot of repeat visitors since it is community based and I would like to make the ads change more often.

Can I add fresh content to my pages that would encourage new ads or is that considered manipulation?

I have also tried blocking ads I think are irrelevent and it takes a while for them to stop appearing. Is there a topic here that explains how the google ads work, such as are they dynamic or depend on indexing etc

Thanks
Caz

[Jenstar]

Blocking irrelevant ads take only a few hours to take effect.

Many people notice a much higher CTR in the beginning, particularly with sites that have a high repeat visitor rate, simply because the ads are new and you get a lot of "curiousity clicks".

You may notice the same ads over because they have a much higher ad budget than others, or because there aren't that many ads in inventory for your keywords on the site. Blocking them could result in lower earnings as well.

As long as you aren't using spam techniques to manipulate the ads that appear, adding fresh content is not a problem. Depending on what you do, you may show different ads after a mediabot visit with the new content.