I noticed some of the heads of my acan are just missing this morning. I've had the acan for over a year and everything else in the tank is doing well. I'll attach some pictures as reference. My only questionable fish in the tank is one spot foxface. I have also had this fish for around a year now. I did get him small though and he has been growing and is currently around probably 4-5 inches. Do the pictures look like the acan is being eaten? Let me know if you need better pictures or more information. Thanks for the help!