I have discovered an easy hack to glue coral frags to your aquascape. Just go to Home Depot or any other home improvement store and get a bag of lava rocks that you would use for a bbq. Instant rubble rock. I have been using this for over a year with absolutely no issues.Works best with coralife rocks as they are the same color. Anyways, glue the lava rock, small piece, to the aquascape, then the coral frag to the lava rock. Awayways looks natural!