I had 2 mandarins in my tank before my yellow tang killed my beloved male (sold that yellow tang right away) and when they spawn they can get overboard and a cover is essential. I fetched my male mandarin on the floor one day after their spawning.
they both rise to the surface and sometime they even jump out of the water, so be aware of this. They need a high tank for that reason in order to properly spawn.
My female is so big and not laying any eggs since the male is gone, so I had to buy another one and he's in quarantine right now, but look at my female! She is in dire need of spawning!
http://www.youtube.com/watch?feature...&v=lP2JT_EboRA
Somebody suggested you get a live white worms culture and this is very good food for them and if you had this, your male would probably be alive still as they usualy go for that food quick. They also love masago (caplan eggs that you find on sushi) as this is part of their natural diet. I do not beleive that mandarin can live from pods alone in such size of tank, especially two.
You should get form white worms and feed them with white bread soaked in milk and Selcon. I enrich my white worms with Selcon and been giving this to my copperband for nearly a year now. He bearely eats anything else and he's fat and healthy. My female mandarin really loves the live white worms and if you get another male there are good chances that he will survive with this food.
As for coral, be aware that some coral will eat pods as well, so it is best not to put anything that will compete with the madarins for food, especialy if that's all they eat.