c02 chamber

hey everyone just wanted to show you guys my c02 chamber...I put dry ice in the bottle and some warm water and the rats/mice on the tub...notice there is an extra hole on the other side so c02 can come out...

https://ball-pythons.net/gallery/fil...5/pb040193.jpg

i cant get dry ice what else could i use

I've used alka seltzer on fruit flies. I'm not sure it will be strong enough for rodents however.

U can use the c02 from pellet guns...

im in ireland and pellet guns are hard got ove hear i heard sumthing about baking soda and vinegar tho