By hungry I assume you mean starving?
You do need a larger tank.
No, it wont eat every pod in the system, it isnt a six line wrasse. People who assume they are this voracious have not kept them that long.
I would stop wasting your money on pods as a sole source of food and teach it to eat mysis.
I have personally helped train dozens of mandarins. Spotted and Greens. Big and small. Male and female.
It is very simple, all you need is a syringe, some rigid air hose, some live brine shrimp and some frozen mysis.
Start with the live brine, the fish will show immediate interest in them. These are not nutritious enough for the fish, but their movement is key to teaching the mandarin the tube means food.
After a few timesusually less than 5 feedings of live brine, the fish will start to learn the food comes from the tube. Then you can start mixing mysis with the brine.
Once the fish is eating the mysis, try switching to just mysis. It has never taken me longer than a week to train a fish, and I have helped many people on the internet succed too. All of them have had similar results.
This still doesnt solve the matter that you need a bigger tank. I would no keep a mandarin in less than a 30 gal system with 45lbs of rock.
Even though you will be feeding it regularly, it will still eat pods obviously. A larger tank will allow you to maintain your pod population on its own.
I never get why people buy bottle of pods time and time again, using it as a disposable source of food. Those bottles are meant to seed your system with a type of pod, not as a weekely food source.
I work at a Reef shop, peraps a little different than a aquarium store depending on your definition, but if you sell these fish then its YOUR responsabilty to train them first and teach customers how to feed the fish. If your shop sells them to just anyone without making sure they understand, which I couldnt see since you yourself dont understand, then you are doing the fish an inustice and should stop ordering them.
Get on your game do your part as a LFS employee to make this hobby better, I do my best everyday.