Hi, i have 3 green chromis, dragonette, and a CBShrimp, and a couple weeks ago we added a Royal Gramma, who seemed to be doing fine until two nights ago. tank has been running since Feb. We do weekly water changes, all levels are consistently good. The past couple of days the Royal Gramma is in his hole in his rock and won't come out even to eat. i also noticed one of the green chromis has been nipped a few times as his back tail has been bitten down quite a bit. I'm worried the Gramma may be sick, but we can't get him to come out to get a good look at him. Any suggestions on whether he's sick or just scared after fighting?