Just wanted to throw in my 2 cents from my experience with the mandarin.
My BioCube was covered with pods, to the point where it bothered me because it made the water look dirty.. they were all over the glass and swiming around, so I thought, I'm gonna get a mandarin and get these suckers! well about 2 or 3 weeks later there were hardly any.. and my mandarin started losing weight and showing signs of starvation, I could see his little bones and felt so guilty. I bought those tiger pods from the store for about $20 bucks each, even got phytofeast to get them to feed and breed and what not but I did not notice any difference at all in the pod population in my tank.
I tried spot feeding my mandarin so many times until I said screw him, I'm going to force feed him somehow and I locked him up in a nursery thing for a few days so I could try to get him to eat frozen or flakes or anything, but failed at that too.. he'll literally be covered in food and will swim through like nothing is there.
so my newest iteration of planning to get this sucker to eat was to hatch my own live pods and get him to eat them somehow... just dumping them in the tank didn't do much for me, they'd swim away before he could get there or he'd come in and blow them away with those crazy fins of his. So I cut the bottom of a bottle and I dump them from the cap end and he swims up the bottle and goes to town (took him like 3 days to figure it out) but I can confirm that he is in fact eating, and now has a ton of food.
Long story short, if I was to do it all over again for the fish and mine's sake I'd go to the fish shop and physically watch him eat frozen or flakes and get the one fish who does. Or know that if he's hooked on life food its probably not going to change any time soon or without any work or patience.