WordPress paginate_links – first page always the same as current page

I have a custom loop in wordpress and have added pagination to it. I have permalinks set to pretty (eg /custom/).

I have the custom loop set up so it can work despite not being the primary loop. Currently the loop works perfectly by appending ?paged1=[number] and taking the loop to the corresponding page.

However the first page number in the pagination is always set to be the same as the current page. Eg the href=

• 1 = ?paged1=3
• 2 = ?paged1=2
• 3 = current
• 4 = ?paged1=4

The same issue as outlined here: https://wordpress.stackexchange.com/questions/87433/strange-paginate-links-behavior-first-page-link-is-always-whatever-page-im-on

However I have pretty permalinks enabled. I tried taking the good advbice in that long anser but didn’t have any luck. This means I want the pagination to work like this

domain.com/page-name?paged1=[number]

and not

domain.com/page-name/page/2

Any advice appreciated. Here is my code

(Code largely used from http://pressedweb.com/wordpress/wordpress-multiple-wp_query-custom-loop-paginations/)

                $paged1 = isset( $_GET['paged1'] ) ? (int) $_GET['paged1'] : 1;
                $args1 = array(
                    'paged'          => $paged1,
                    'posts_per_page' => 18,
                    'post_type' => 'post',
                    'orderby'=>'date',
                    'order'=>'DESC'
                );
                $query1 = new WP_Query( $args1 );

                while ( $query1->have_posts() ) : $query1->the_post();


                    blogside_loop_output();


                endwhile;

                $big = 999999999; // need an unlikely integer

                $pag_args1 = array(
                    'format'   => '?paged1=%#%',
                    'current'  => $paged1,
                    'total'    => $query1->max_num_pages
                );

                        echo paginate_links( $pag_args1 );

                    if ( $paginate_links ) {
                        echo '<div class="pagination">';
                        echo paginate_links( $pag_args1 );
                        echo '</div><!--// end .pagination -->';
                    }