Haha, after hours of trying I finally decided to write a post.
And after another five minutes I figured it out.
You have to set the link type to “attachment” and add the attribute target with the value “blank”
[su_tab title=”Titel”] [su_custom_gallery source=”taxonomy: media_category/16,17″ limit=”100″ link=”attachment” target=”blank” width=”200″ height=”120″][/su_tab]