okay, I'll give it a try. Would I replace the code entirely with this below and if I had more page ids to include, do I list via comment? (sorry, Im a newbie):
<?php if(is_page(14,16,18)) { wp_nav_menu( array('theme_location' => 'secondary-menu','menu_id' => 'nh-nav','menu_class' => 'sf-menu')); } ?>
<?php
if(is_page(13,20,30)) { wp_nav_menu( array('theme_location' => 'third-menu','menu_id' => 'ma-nav','menu_class' => 'sf-menu')); } ?>
<?php
if(is_page(15,30,31)) { wp_nav_menu( array('theme_location' => 'secondary-menu','menu_id' => 'main-nav','menu_class' => 'sf-menu')); } ?>