Low light corals

[Scavenger]

The kenya tree stated above is a great choice in my opinion. Also I'd give thought to a leather or even a low light lps such as torch, or bubble. I've had these in darker areas of my tank and they do fine.

I would avoid any poly type species such as button or star, as well as any mushrooms. I personally find they always know the grass is greener over there and head for the prime spots you want for your showcase corals.

This is just my opinion, hope it helps.