posts shortcode prevents page from paginating

The original developer who added the codes is not involved with this site, so I am trying to make sense of it. This blog stream page has this code:[su_posts posts_per_page=”999999″ tax_term=”1895″ order=”desc”]. If I change the posts per page to a reasonable number like 10, it does break it at 10, but there is no “more” or “next” or other pagination to get to the older posts. If I remove the shortcode, and set the WP reading settings to this as the blog page (it’s currently defined as a regular page), I can get pagination, but the images go to the full column width, way too big. Is there more shortcode that would create pagination? Pagination plugins that I’ve tried do not work since they have to override existing pagination.

The page I need help with: [log in to see the link]