I kinda followed the culturing crix on container. Used like a small tote, used tape, and instead of screen, I just knifed holes. Although my crix are just pin head size, my local petshop has a bin (left open) with the tape around, and they don't get out. My tote (storage bin) was about 8$ and can fit over 200 adults, guessing, and I have 500 pins. Reminds me, I need another bin.