You have a sample pic?
Usually sand anemones stays at one place when u place them. I have a sandbed thus i dig a hole for it. Need high/moderate lighting. Have 2 in my tank.
And i feed mine daily when i feed my fishes. Mine is a bright pink sand anemone. And by luck its hosting a clownfish. Dont usually happen...
The other one just lepak beside a plate coral and funny that the plate coral didnt go to war with it. So they live in peace touching each other but no stinging sign from each other