Attaching Chalice to bare bottom

[Fourstars]

What kind of glue would you recommend for attaching a chalice to the glass bottom of a bare bottom tank. Want them to encrust the glass but the snails and hermit crabs keep moving them? I'm thinking epoxy probably won't stick to glass?

 

[cloak]

Do you have any Coralline algae growing on the bottom? If so you might want to use some super glue gel and attach the frags to these spots. The Coralline algae gives the glue something to grab onto as opposed to just bare glass.

 

[Fourstars]

Good point. I'll Try gel and use a coralline patch. Thanks!