Engineer Goby Not Eating


Reefing newb
Hi everyone, this is my first time here on living reefs so I am looking forward to meeting you all.
My engineer goby has been in my 30 Gal for 3-4 days and it seems healthy by sifting sand under rocks but it never comes out though. Even at feeding times. But it seems healthy and darts from rock to rock from to rock and is pretty social towards my saddleback clownfish. But it isn’t eating though. I suppose I have some experience in fish that don’t eat or refuse to eat because my clown goby used to reject all food so I fed it rotifers and it took some per day and smoothly transitioned to copepods and then mysis and brine shrimp(all frozen BTW). Hope I left important info for you if you want to help me. But a big thank you anyway.