Not an expert on sebeas, so take my advice with a grain of salt (no pun intended).
If it has not attached by the time you get home, or has been pushed around by the water current again, look for a place in the tank where there is very gentle water flow and try to plant it in some rocks there.
For more info, here is RC's Anemones & Clownfish Forum....
http://www.reefcentral.com/forums/fo...?s=&forumid=36
Also, here is their Anemone FAQ....
http://www.carlosreef.com/AnemoneFAQ.pdf
Good luck
