I have a small Dubia colony, but my frogs dont like them a whole lot. So they're an occatitional feeder.Overall they are a good feeder up there with earthworms.
You can divide a large tank with a piece of plexiglass or actual glass securly siliconed into place. It must be completely sealed so neither frog can possibly get to one another. Also you will need to make it where they cannot see each other for safety reasons.