It seems that the search function is not working. If you are like me and live and die by the search function. You can use google. It will not as good as the server search, but it will work
Just go to google. Type in your ->
search item site:http://www.plantedtank.net/forums/
180 gallon setup site:http://www.plantedtank.net/forums/
Google will search it for you.
Hope this helps.