I use a 10 gallon tank with a screen lid. Easy to clean. The box is small enough to fit into the 10 gallon. Just shake them in. Tip the 10 gallon at an angle and any dead crickets or feces will slide to one end. I scoop them out with gloves.

I just tap the egg cartons over a plastic cup to get some for feeding. You can add your calcium or mvi pinch to the cup and give it a swirl or two to lightly coat. I just get an inexpensive pack of 5" smooth plastic cups from Walmart. That way if you have to set them down for a minute that don't climb out.