I just shared what I did in another thread. LOL
I had a massive outbreak in my 55g that had no livestock in it so I nuked the tank with ammonia. I let it sit for a few days and then did some 90% water changes. Not one anemones survived. Also, all the ammonia still in the tank caused it to cycle which was a nice bonus.
I tried the boiling water soak with the rocks and letting them sit outside on the pavement but the anemones still came back. :-(
I had them everywhere too, in the sand, the skimmer the filter, everywhere. I actually had thousands of them, there was like a field in my tank of them.
Good luck, hope you guys get them!
180g- Mostly BIG fish and some coral. ~80g Nuvo- My coral tank with "happy fish"~ 90g- FOWLR Not the not happy type of fish~ 125g- Freshwater Malawi Cichlids ~10g- Nuvo- The refugees from the Ich of '18