There could be. The angel could see the tang as a food competitorsince they both can pick at the rockwork and vice versa. But if your tank was large enough and had a lot of hiding places I would think it would work. The key word is "think". I don't know how large a mimic tang gets or how aggressive they are. Since pygmy angels don't grow very large, you could add a small pygmy angel first, then the tang.