I could be mistaken, but I do not believe that capnella is a member of the leather family. But to answer your question, yes, it is more damaging than other leathers as far as stings go from my experience. I had a frag of capnella wipe out an entire colony of xenia. just from brushing against it in the current. The capnella wasnt even phased by it. I have mine in close proximity with other corals, but no contact. I have to keep an eye on it though. I dont think that just being in the tank is any worse than any other coral, but if it touches another, it will probably win.