I have an ornate leopard wrasse who I've never managed to train to eat frozen foods. I've tried everything under the sun with no avail. With that said, mine is in a 75G tank with a Mandarin goby and they are both fat and happy living off the pods in the tank. I dose phyto and also have a culture of pods I use to keep them fed. I would imagine in a 180, worst case as long as you can get them through their QT that your pod population should be good as long as your not running ULNS.
Make sure to QT them and treat for flukes, since they can be very prevalent in the Leopard Wrasses. QT in a tank with a small container of sand since they are sand-burrowing wrasses. Most people say they have luck starting them off on foods using live blackworms, or ova. When picking out your wrasse if buying it at a LFS, make sure to check it's mouth carefully. Some fish sustain damage to their mouths either trying to dive into the glass bottom or during shipping. If they have damage to their mouths, it's sad but take a pass and wait for a better specimen since they have a poor prognosis :(