Well, my tank is not too stable since I don't have a calcium reactor, but the temp is stable, and I test and add as necessary for alk and calcium. I'm going to put the fresh water into the sump from now on. I noticed about this coral that it did not encrust onto the rocks like the montipora. I had it wedged pretty well, but once in a while it would come loose. I guess after so much stress it gave up. I might try again when I get better parameters. It's so expensive to lose. Thanks for your advice.
Nothing else I can think of would cause this.
Kay