Catpicklesdog
Hindsight is a wonderful thing!
I had the same problem with one at my LFS so we directed a powerhead at it (it worked when I wanted to move a previous one) unforunately I didn't have time to wait so I bought the rock as well!!!
ice works sometimes. But it will go back to where it wants, so why bother. It won't stay where you want it more than likely.