You most probably need s-strain rotifers for mandarin larvae. S-strain is not going to be as easy to culture as L stain - S strain is crash prone. You also need to learn how to culture two or three varieties of phytoplankton (nanochloropsis and tetraselmis for sure.) You also need to learn to hatch baby brine shrimp and collect them at the right timing before they consume their own yolk sacs.
My mandarin pair also spawns regularly, too, but it would be a pain in the neck to capture eggs because they scatter them fast near the surface. I suspect the eggs go right down the overflow to the sump.
Breeding and raising fish requires a lot of dedication. Feeding several times a day and a lot of water changes to start with. Even fresh water egg spawners such as discus, tetras and angelfish require a lot of work and space (I have done plenty of these - to the point that LFS owners hide from me when I show up with a bucket.)
I suggest that you first try an easier fish like Bangei cardinals or clownfish first before you attempt difficult ones like Mandarins.
If you are still determine to try your hand at breeding mandarins, contact NicoleC in Alabama Reefers forum here on RC and ask her for the name of breeder friends who are breeding them. They should be able to tell you what you need to do.
Tomoko
