Hi guys,
After numerous people told me that I should be able to construct my own CO2 chamber, I've decided to give it a go.
I wanted your advice on the parts, as I will be ordering almost all of them online.

So far, this is my shopping list. I'd appreciate your feedback on additional things / parts needed or if what I've selected won't work. I will need to be able to gas about 12-14 rats at a time (probably 1 litter at a time).

CO2 tank (planning on ordering 2 to have a backup)

Coiled Remote hose with slide check (I'm assuming that I will be able to control the flow of the CO2 with the slide check valve?)

Airtight bin (I'm assuming that I will drill an air release hole/s near the top) Is this bin large enough or too large for the number of rats I will need to euthanize? If you have other suggestions I would love to hear what bin you use.

If you have any other feedback or input, please feel free to post! I am not "handy" at all and trying to build this is definitely a big step for me. I'm a little paranoid that I will mess up something, thus resulting in the CO2 chamber not working properly.
Thanks for your time and help!