Most of the softies do not glue well. The rubber band method works OK as long as you don't get it too tight. You can also attach them with a piece of bridal veil. Cut a strip, place it over the coral (just tight enough to hold it), and glue it to the rock on both sides. You can also pin them to a rock using super glue and a plastic toothpick. Or, you can just lay it on some rock rubble and let it attach on its own. Then glue the rubble, with the attached coral, to the rock of your choice.
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