Hi Christian,
Unfortunately there is no setting to configure this. The default value is 30.
If you really want to, you can try modifiying the default value in this javascript file and then recompile javascript on your site(http://take.ms/AMP3m).
JoomlaFolder/media/com_easyblog/scripts/composer/tags.js
Do note that the changes applied to this file is not protected from future updates.

I did not find the file you are sending me. In the latest version, it's called how?

Hello Christian,

It is not possible to configure this currently. We'll see if we can add this as a settings on the next release.