chaeto is a good choice.
IME Mexican caulerpa and "grape" caulerpa seemed to prefer higher light. Whereas caulerpa prolifera did better with lower lighting.
Gracilaria is another good choice.
the hard algaes like halimedia need reef light conditions of high light calcium and the like.
The refugium can be just a simple tank partion with the livestock in front and the macro behind the partition.
I sure there are many other macros that would work but my experience is limited to those. They are inexpensive enough to experiment with and see what works for you.
my .02