There's something called a POD hotel. I believe it's a trademarked item, but Google it to see the concept. I just saw a new version came out at macna on @melevreef channel. Basically, it provides a safe space for the pods to breed in your tank and can be hidden in the rocks. Dump pods bottles in there, add some phytoplankton via turkey baster, and hopefully that will help jump start your tanks supply. If you put it somewhere you can watch, once your Mandarin is accustomed to going there to eat, you could try adding some frozen food as well. Melevreef also had a good Olive jar idea for feeding mandarins frozen without feeding competition.
I did a 2 to 1 ratio the first 2 months. 2 bottles every other week in the tank 1 in the sump with my chaeto. This allowed some to bread in safety other food. As others said remove any filter socks or other media so you don’t filter the lil guys out on accident. Some will take to other food like ROE raw oyster eggs , mysis, or brine shrimp. Mine didn’t. Don’t be discouraged as there people out here that have kept them for years I just was not one of those lucky ones sadly as that’s my wife’s favorite fish.
