I have 3 zoa that I purchased on what looks like ceramic tile plugs. They have grown a bit and I'm not sure if I can or should pull them off the plug. The issue is the plugs have a very smooth bottom and no matter what kind of glue or where I glue them, they always end up on, in, or upside down in the sand, knocked off by a fish or the current. I've tried looking this up and only found one video that doesn't explain how to deal with my particular issue. Any advice?