well this is way late of course...
But Cualerpa is nasty stuff.
1) it can go sexual (which means it dissolves into a bunch of reproductive cells) when this happens you can kiss everything in the tank good bye.
2) it is noxious
How do you control it?
Get in there, rip as much of it out as you can. every last shred you can get your fingers on.
Do a massive water change.
Biological control of Caulerpa is almost impossibe - if there is something else palatable for a grazer, its gonna go for it.
you may have luck with Elysia subornata, a sea slug that eats caulerpa if you can find it, but I find that doubtful.
The only way I have ever heard of it being eliminated from a tank is the old fashion way.
pull your rocks, remove your coral put in a holding tank. Manually remove all the cualerpa, brush your rocks with a stiff bristle rock.
If you have a sand substrate, bye bye, replace it it only takes a shred of this stuff to restart.
Rebuild the tank, and keep your nutrient levels nearly non existent to keep it from gaining a foothold again.
Your other option is to remove everything you want to live, and deny the tank light for a week or 2 until everything becomes a noxious soup. drain it, re-cure your rock, and start over.