Our fiberglass pool has the exposed fiberglass lip, there is not any coping on top of the pool. The concrete deck butts up level against the edge of fiberglass lip. In most places the concrete is tight up against the fiberglass, but some areas have shifted over its' 13 year life. In those places there is a gap anywhere up to 1/2" between the two. Should I backer rod and caulk these areas or just leave it be? Can anyone with a similar style advise if there is caulking around the edge of their pool?