they aren't technically cories. And they do get a bit bigger than peppered cories. I've never kept the green ones personally but I do have a few peppered in one of my tanks.
But as far as I know they are basically the same feeding-wise as other cories.
I like my Brochis, I call them my little dinosaurs. They do much better in a large group, 5 or more, otherwise they are pretty shy and hide a lot of the time. But they are gorgeous when they get big!