Dispaly your Custom post types in your feeds

// Show posts of ‘post’, ‘page’ and ‘blog’ post types on Tag page
add_action( ‘pre_get_posts’, ‘add_my_post_types_to_query’ );

function add_my_post_types_to_query( $query ) {
if ( is_tag() && $query->is_main_query() )
$query->set( ‘post_type’, array( ‘post’, ‘page’, ‘blog’ ) );
return $query;
}