I had the same problem today. Used ice, lifted rock out of water, used a powerhead and the anenome would not budge. So I used the nail filer from the end of the nail clipper and slowly pried it off. I mean SLOWLY. Everytime I inserted the filer under the base I lifted it no more than a few mm. Anything more may tear into the base. After 30 minutes I was able to remove the RBTA safely. Now its in another tank healthy with no visible stress