Hello ObAtAnG.
I have only been in this hobby for about six months so others with more experience may offer other advice.
I have a Yellow Headed Sleeper Goby that I drop 3 or 4 shrimp pellets in for him to feed on. He will chew on them and spit them out then chew on them more as the water softens them. I sometimes soak them with a few drops of garlic juice or put them in a small cup of tank water to soften them.
He has adapted to this feeding routine very well. The reason that I feed 3 to 4 pellets is that my cleaner shrimp will also take one of the pellets and sometimes the crabs will eat them. You may want to try one pellet at a time to see if it will work for you.
The Goby will sometimes eat the flakes and frozen shrimp that I feed the other fish but they rarely let any food reach the bottom.
The Goby does a great job of keeping the top layer of my sand nice and clean too. I realize that he may feed on some of the stuff he sifts from the sand but I feel better seeing him eat the pellets. His stomach seems to stay full looking and not compressed or looking like he is starving.
Good Luck