I Purchased a rock a month ago with 2 patches for half price at a LFS of Zoa's on it the one patch is doing great but the on growing on the clam shell seem to be struggling both patch's had some Necrosis on them I used a scalpel to remove as much as possible it seemed to work for both but now this on seems to be slowly dying? can I remove anymore dead tissue to save it or should I just wait it out?