Katydids are a bit like green grass hoppers I guess, but they are a leaf type shape, I have one in my album if you have a look. Mork is thinking about eating it but its too big for him, i put it in for Mindy. Locust are really easy to breed if you have the time. They don't need heat and they don't smell. I put mine in half sun every day if we have it. I put them on the widow sill. Mine are a different breed to yours but mine just eat grass, apple, bran fakes, bamboo. As long as they have a constant food supply that is fresh then they do well. You don't need water either so there's no issues there. I have photo's of them in my Album too.