I also have a eretmodus cyanostictus - goby cichlid - Congo orange - same as yours. I wasn't going to go with gobies in my tang tank, but I ordered 2 anyway. I lost one the first night from the shipping. But this guy really grew on me. He's my favorite. He comes right to the glass now to say high and yes, he hold his own. My dominant male Xenotilapia Ochrogenys likes to get bosses and push fish around and chase to corners, but he gives him what for and won't be bullied. He can go from light colored to dark, dark, almost black and bright orange depending on his mood. He's cool. My buddy. They are algae eaters. I drop algae zucchini rounds for him and he munches on the algae in the tank. Make sure I got some good algae going. He'll eat cichlid pellets, too.