Easy Pipefish?

[Enigma]

Is there such a thing as an easy (or moderate) to care for pipefish?

I'm starting to mull over the building of a frag/growout system, and I'm thinking that pipefish might be a nice addition to it. I like the thought of having a natural predator in there, but I'm also very conscious of the challenges of keeping them. Has anyone had any success in getting any of the species to eat frozen?