I put my first pair of seahorses in a 40g tall. Within a week, there were no pods
of any kind left. You will never build up a pod population with seahorses in a tank, and if you build them up ahead of time, the same thing will happen that happened in mine, gone in no time at all.
I waited years to get captive bred seahorses and that is all I would use.
I have kudas and reidi's in my tank and both will basically only eat the frozen mysis, but even then, they only pick out the ideal specimens and I have to vacuum out the rest before they pollute the tank.
Like a previous post mentioned, check out seahorse.org.