Fish that compete with Mandarin Dragonets

I currently have a 70G aquarium and I plan to add a 20G sump/refugium to it soon. I really want to add a Mandarin to it. I know that they need a huge supply of copepods and I wouldn't get on until at least a year after I set up my refugium, so I would have an good supply of them to feed the Mandarin. I also plan to get one from my LFS AFTER seeing it eat other foods, like frozen brine shrimp (so I don't starve the little guy). I would also add a population of pods after I set up my fuge, so I can give them as much time as possible to maintain a large population.

By big question, that I've had trouble finding an answer to is, what fish should I avoid that would compete for food with my possible Mandarin?

I know I have to watch out for Coris Wrasse, aggressive tankmates, and any other Dragonets, but I can't seem to find a reliable source of other fish that out beat them out for food.

I currently have 3 Firefish and 1 Yellow Clown Goby, 4 Hermit Crabs, 3 Nassarius Snails, and 3 Astrea Snails. I have ideas of other fish that I would like to get someday, but I want to see if my want of a Mandarin would be incompatible with anything I may get in the future.