He likes whitebait and mysis, brine shrimp anything really he has been a hardy out the front all the time fish, he shares a cave with Ptereleotris zebra (Zebra Dart Goby) You can see them peeping out side by side so cute, the Zebra is more timid but is getting better. Anyway thats why I can't understand whats happened I think he must have been trapped.
I could recommend this fish but he does need to sift sand, I have been feeding my other sand sifter (big boy) by hand since I put the new sand in.