if you're feeling adventurous, I cut the "prongs" on the bottom of the plugs off with a dremel, then epoxy it down. That way I don't have to restrict it's placement to a hole.
But you gotta be careful that none of the hot plastic makes contact with the coral as it flies off. And one time I lost grip of the frag and the dremel sent it flying about 15 feet across the room. It's doing ok now, but it really shocked me then
