I do have a small duncan but it has not gone anywhere near it yet but i will keep that in mindThe only coral for so far that reacted negatively towards my nem was my Duncan. I moved the Duncan
So you know... in my case the Duncan that was being touched by the RTBA reacted by not extending the fingers of his polyps on the side he was being touched. He sorta just kept them folded up real tight. I only allowed it to go on for two days before I moved the Duncan. I do not know if any damage would have occurred if I left it.I do have a small duncan but it has not gone anywhere near it yet but i will keep that in mind