My fox coral has shrivelled up and I'm not sure what to do...In the past month we've done several water changes (to eliminate excess nitrates, which had gone up to nearly 20ppm and to syphon some flatworms that we discovered on a live rock), but otherwise our routine remains the same. Water quality (now) is excellent, with nitrates down to 2.5 and other parameters as nearly perfect as you could get them. Any suggestions?