I have had a montipora cap and montipora seasons greetings (undata?) recently die very suddenly when they were thriving previously and growing to new rock. I have acropora right next to the montipora that continue to thrive. I remember reading something about montipora eating nudibranchs. Tonight I took this video when feeding the tank. Can anyone help identify this critter and let me know if it is the source of my problem? If so, what is the recommended treatment? The critter appears at about 10 secs into the video in the little cave at the top of the screen. I have dipped every coral that I have ever placed in my tank with CoralRX for 10 minutes. Thanks in advance for the help!