Reported this morning by an end-user from DCCEEW: the site's landing page is still trying to link to the old /tools/ page, and that link is now broken since that content moved to /outputs/.
The link is on the very front page of eReefs - eReefs: It is the ‘Read more...’ link under “Diving into eReefs marine information”
Please correct that ASAP, and also search the rest of the content pages to make sure any other instances of the old URL have been corrected.
We should probably also look at supporting redirects for any page-moves in the future: it looks like there's a Jekyll plugin for that