I don't have the sidebar navigation active at the moment, as this will affect all the other product pages.
All the product pages have category navigation at the top, however its only visible in /tinned-fish because all the other product pages have no categories or are hidden.
When category sidebar navigation is selected across all pages, the pages with no categories have a big amount of blank space at the left, which is annoying.
That's why I only want the category sidebar navigation in one product page.
Hope it all makes sense.
Thanks again!