you wont want anything else alive in the tank, Live Rock has critters, some of which can kill and eat the baby seahorses. You dont want much of a flow, plus live corals will sting them.
seahorse.org - Tankmates
^helped me out a lot when I was studying how to take care of them. But for now I dont think Im ready to grow the live food every day and everything that it takes to take care for of them, maybe when I win the lotto and can sit at the house all day