you probably already have a population of pods in your tank. pods are small crustaceans that inhabit your rocks and sand. they are a primary food source for plankovore's (fish that eat plankton) and baby fish (fry) In order to be able to successfully keep a mandarin you will need about 100 lbs of live rock, most people keep a good supply of pods going by using a refugium. the reason for this is that there is usually no predation in the refugium and the pods will be able to multiply uninhibited. They are sent into your display a few at a time thru your return pump, continiuosly feeding your tank. the macro algae that fishman72 was refering to is called chaeto. it grows like spagetthi, and has a lot of surface area to it. it is very dense, and an excellent house for pods. they can freely reproduce in it with little fear of being eaton, again especially if in a refugium. you can also buy live pods online. do a search for tigerpods.
