I have put live brine shrinp in my tank and I still never see my mandrin goby eat...is there any way I should feed him other than just putting in a bunch of live brine shrimp, my fire shrimp loves the brime shrimp...
mandarines need a diet of copopods--unless your system is well established or you have a dedicated refugium for producing them, it will slowly starve to death
sorry to be so blunt but your best to take it back to the lfs if you can,
You can order pods, but the mandarin will likely eat those until they are gone as well. I would take it back until you get a population established or you will have to buy pods online quite often. It gets expensive.