Just my observation, but I don't hear much about strontium these days. Once people started using it the Elegance started binding to their shells. Are you dosing strontium? It may help. Sorry if my info may be out of date but I had to take a break from reefing due to my job.
I actually kept one for six years prior to breaking down my tank, I gave him to a Dr. friend of mine. He was still alive as of four years ago (or so I was told), that croral would have been 22 yo at that point!
Regards
Neil