i need to euthanize some mice before they get too big, i got some really small bps a spider and a het pied both female,

i am planning on using dry ice, if u know of a link or can explain it becasue ive searched and couldn't find a good one, i suck a Google- ing for some reason,

i was brainstorming on how to do it, i dont think i want to use a hose/tube to transfer the Co2 unless i can find one around the house, im not looking to spend a lot of money when i can do it with out it and im not going to be doing this often, im sure i have enough supplies around to rig one up.

i was thinking that i would use 2 sterilite tubs put a small one in a bigger one - have the dry ice in the small or big and the mouse hoppers in the other.
also what size tube should i use if i have to, cuz i have the water tubes for automatic watering for rat racks



Also how can i switch hatchlings from mice to rats, on my 0.1 het albino she wont eat rats unless i put the rat weanling in my mice bedding and then she will eat it but she is mostly hesitant when she strikes