Perhaps it's just different methods of approach. I've never purchased a mandarin with the sole intent to let them live off pods in my tank, so I was determined to train them. None of the mandarins I've purchased have ever taken longer than a week or so to be trained onto at least one frozen foods. Call it luck? Or maybe food choice?
I'm just basing it off my experience and what's worked for me. The first time I was nervous and thought it would also take months. Imagine my surprise when using live brine to acclimate to frozen took less than a week.
Here's what I think went right for me:
-I chose my first mandarin very carefully. Anecdotal reading suggested that female mandies are easier to train, so I waited until my lfs had a relatively fat, female mandarin.
-I had prepared a variety of frozen beforehand
-Once the female was trained, I personally believe that my subsequent mandarins learned by watching her. In effect, my first trained mandarin helped "train" my new mandarins.
-Lobster roe. Or Nutramar OVA. My third mandarin was trained to frozen by the 3rd day on this stuff.
-Smaller tank: Being that all my mandarins were trained in a 20 gallon, I think the smaller space allowed me to give the focus and attention to the mandarins, instead of losing them in a massive tank.
I'm not trying to be combative, I'm just suggesting alternative methods to the traditional "mandarins only eat pods, without pods, they die" mentality. This discourages individuals with nano tanks from attempting these pretty fish as they get the impression the ONLY way to keep mandarins is to have a 150+ gallon tank for just one mandarin, which frankly, I do not think is true. There's another forum with a thread where dozens of people have trained their mandarins to eat frozen.
Yes, but training them takes time (it can take months or never happen at all) and you have to be prepared with foods on hand and a good pod population already in the tank in case they don't immediately take to the frozen foods. In your original post you make it sound like a piece of cake, as if you could just put them in a tank that's been setup for a month with dry rock and have them eating frozen mysis immediately, and I felt that was misleading.