i don't believe mandarins have begun to be tank raised. i've read articles on people having reports of spawning, but as for all marine fish getting past the larval stage is the most challenging part. you must find a type of food they can ingest and nutritious for them at the same time. types of rotifers are the key and culturing them, but they're are many different types. who knows in about 10yrs. maybe about 40% of the species available can be offered tank raised vs. the 5% offered today for sale.
i think mandarins will come soon than later as you can tell male from females and be able to form a pair.