I also use a combination of "crazy glue" and epoxy but I use the reef stuff. The reef glue is actually cheaper than crazy glue, you get way more for about the same price, from what I've seen anyway. And the epoxy isn't too bad either plus it comes in purple and you know it's 100% safe (glue is also available in purple). This is what I use:
Plug/rock - glue - epoxy - glue - coral
HTH