It dosen't look like a detritus worm to me. And in any case detritus worms generally manifest an established tank that is overfed. This guy has just set this tank up! How would he get detritus worms so quickly?
I think to be on the safe side, before you get fish in there, it would be best to do as Tom suggests and empty it and clean thoroughly.
hey unrelated - saw your post a while back on starting a new sump on a 180. had a few questions for you if you still have that running. my # is 2018359561