I would like to get a spotted mandarin or a green mandarin sometime in the far future, how can I get a really high population of copepods and amphipods for them? The fish in the tank are 1 yellow tang, 1 coral beauty angel, 3 damsels, 2 turbo snails, and a peppermint shrimp and cleaner shrimp. It's a 50 gallon tank, and right now I only have a few pounds of live rock. Thanks!