How to: Build A Homemade Co2 Chamber

[JC]

Hello,

In this tutorial you will learn how to build your own CO2 chamber for under $10. This is the way I sleep/knock out all of my invertebrates for my experiments. This tutorial covers MY own personal method which I have use, although may be other methods available.

You will need the following:

1. (1) 2 liter bottle.

2. (1) Three foot fish tank air line tube.

3. Sugar.(one cup)

4. Yeast.(one tablespoon)

5. (2) 2 liter bottle caps.(One with hole and without hole)

6. Clay.

7. A small delicup with a lid.(Pictured measures 4LX2H)

8. A drill.

9. Water.

STEP ONE:


a) Fill up one cup of water(warm) and add the 1 tablespoon of yeast and stir it for 1 minute.

b)Pour stirred yeast into the 2 liter bottle.

c)Add 1 cup of sugar along with three cups of warm water to the 2 liter

d) Add enough water so that at least 3/4 of the 2 liter bottle is filled.

e) Cap the bottle well and shake it for 15 seconds.


It significant CO2 production will begin in one hour after shaking.



STEP TWO:


a) Drill the 2nd bottle cap to fit the plastic tubing.

b) Insert tubing just 1-inch deep and cover seems with clay on both sides.

c) Make a small hole in the middle of the deli-cup lid.(I carefully use a screwdriver to make the hole)

d) Insert the other end of the plastic tubing about 1-inch into the deli-cup lid. Cover all seems with clay

Assemble it and you are done!

The spider inside the delicup

The Reaction:


C6H12O6 ----> 2 C2H60H + 2 CO2





-The Pterinochilus murinus female pictured here was out cold at exactly 1:24 hours after being exposed to the CO2 in the chamber.

-5" centipedes exposed to this system for 1 hour have been been completely knocked out for up to 00:30 hours.

-Knockout time will vary according to to the animal's size and reaction effectiveness of your yeast.

-A good rule of thumb for figuring out whether the spider has been knocked out or not are the spinnerets. Drooped spinnerets and relaxed chelicerae are a good indicators that the spider has lost motor control.


Tips:

Do not expose the invertebrate to this system go more than three hours. The animal may adapt to the oxygen levels and regain consciousness or expire.




WARNING:

Do NOT completely cover the top of the bottle for long* periods of time or it will explode.

Do NOT allow the liquid to completely fill the 2 liter bottle.


Disclaimer:

I am neither chemist nor a biologist! This is my own experimental system that has works for me. Use at your own risk.

 

[advan]

Nice write up. :clap: Thanks for posting.

 

[Rabid538]

This is very helpful, thank you. I might try this on mice so that I can pre-kill them for my snake. Do you know if this method can be safely used on slings?

 

[JC]

This is very helpful, thank you. I might try this on mice so that I can pre-kill them for my snake. Do you know if this method can be safely used on slings?

Rabid,

I have honestly not experimented with slings. But it would be a but trickier. First, you would need a smaller delicup, but I do not know the sleep/wake up time.

Second, you will have to carefully monitor the sling's responsiveness as you conduct the experiment to make sure you don't loose it.

I would personally not recommend knocking out spiderlings though.

 

[Rabid538]

Rabid,

I have honestly not experimented with slings. But it would be a but trickier. First, you would need a smaller delicup, but I do not know the sleep/wake up time.

Second, you will have to carefully monitor the sling's responsiveness as you conduct the experiment to make sure you don't loose it.

I would personally not recommend knocking out spiderlings though.

Okay, thank you very much. I don't think I will try it then.

 

[Kirk]

Dry ice would be a quick carbon dioxide source. Using your set up, place a piece of ice in water. Dry ice is available from some grocery stores, ice cream shops, etc.

 

[JC]

Kirk,

Thanks for the advice! I will see to use it my next experiment. But I think the water vapors may be a minor problem.

 

[Hobo]

Thanks for the guide.
Hopefully it'll be something I won't have to try, but it's good to know I have a guide if I do

 

[sjl197]

Huh, cool idea.

Kirk, i find that dry ice is often slightly difficult to either find or keep stable whilst deep in the jungle experimenting on spiders, and airplanes dont like carrying CO2 canisters.... whilst a bag of sugar and a bag of yeast, plastercine, and plastic tube will fit in my bag nicely going into the jungle...i guess i can build the rest in the field! I think several hours of boredom and a pen knife will replace the drill, etc.

 

[Kirk]

Huh, cool idea.

Kirk, i find that dry ice is often slightly difficult to either find or keep stable whilst deep in the jungle experimenting on spiders, and airplanes dont like carrying CO2 canisters.... whilst a bag of sugar and a bag of yeast, plastercine, and plastic tube will fit in my bag nicely going into the jungle...i guess i can build the rest in the field! I think several hours of boredom and a pen knife will replace the drill, etc.

I've done field work for 30 years, and wouldn't expect to come across grocery stores or ice cream parlors selling dry ice in jungle habitats. Yet, how the context of my reference to dry ice could be taken so far out of context is paradoxical.

 

[Tym Hollerup]

I might just be stupid here, but what kind of "experiments" are you performing on your T's? Maybe it's just me, but I'd much rather leave my T's alone as much as possible. :shrug:

 

[super-pede]

Why havent I thought of this?!
simple yet brilliant!

 

[BrynWilliams]

A cheaper source of CO2 would also be using Bicarbonate of Soda

Whack it into some water et voila, bubbles of CO2. Accelerated if you want by a few drops of something acidic in the water (vinegar, lemon juice etc)

Hope it helps!

 

[JC]

BryWilliams,

Defiantly noted and scheduled! Thanks!

 

[Nerri1029]

A cheaper source of CO2 would also be using Bicarbonate of Soda

Whack it into some water et voila, bubbles of CO2. Accelerated if you want by a few drops of something acidic in the water (vinegar, lemon juice etc)

Hope it helps!

This is my method as well.

Sodium Bicarbonate ( Baking Soda ) and Vinegar.

I can start immediately, and I can put a T under in 5-10 minutes, I can also generate enough CO2 to not have to transfer them to a deli container.
I tape up the holes, and put saran wrap over the top of the container. you can extract defensive species from tight places this way.

SEE: Link
It's the second half of the presentation, so just skip to that part.

---------- Post added at 03:31 PM ---------- Previous post was at 03:25 PM ----------



With the bicarbonate method you also do not have the ethanol fumes to worry about either, or the mess of the yeast.

 

[JC]

This is my method as well.

Sodium Bicarbonate ( Baking Soda ) and Vinegar.

I can start immediately, and I can put a T under in 5-10 minutes, I can also generate enough CO2 to not have to transfer them to a deli container.
I tape up the holes, and put saran wrap over the top of the container. you can extract defensive species from tight places this way.

SEE: Link
It's the second half of the presentation, so just skip to that part.

---------- Post added at 03:31 PM ---------- Previous post was at 03:25 PM ----------



With the bicarbonate method you also do not have the ethanol fumes to worry about either, or the mess of the yeast.

Excellent. Good to hear others are using this method as well. I may do a tutorial on this method as well and post it here.

Also, if anyone wants to do a tutorial on one of these other methods feel free to post it here. Thanks.

 

[zonbonzovi]

Awesome writeup, Nerri! I had trouble with the reaction of the fluids shooting through the tube & flooding the chamber where the patient sits...too much baking soda? I bought a soda stream instead. I found that equal doses of CO2 could have very different effects for different but closely related creatures(I was knocking out centipedes for sexing). Very unnerving when working with large specimens only to have terminal legs suddenly grasp a finger while you're trying to get a snapshot. Any speculation on why some things go under easily and others seem to resist?

Your photo methods in the writeup: is there an ideal working distance from the scope's eyepiece?

 

[BrynWilliams]

CO2 is heavier than the majority of the gasses in air, and thus will sink to the bottom of the enclosure. Think cheap theatre smoke. (this was nicely illustrated in Nerri's presentation.

So different diameter/size enclosures will require different volumes of CO2 to 'immerse' the specimen. Equally, where the specimen is relative to the bottom of the enclosure will affect how long it takes to anaesthetise. Also, the temperature of the day will affect the rate of diffusion into the surrounding air, however this won't be a massive factor.

 

[JC]

Also, the temperature of the day will affect the rate of diffusion into the surrounding air, however this won't be a massive factor.

Also, it will affect where the CO2 is settling. Will see how I can manage it to level it with the animal's breathing efficiently.

Have any of you thought about exciting the animal's metabolism, then shocking it with a sudden burst-introduction of CO2? It should work most effectively.

 

[HotPocket]

this is a great write up. I may try this to chill out feeder rats for my royal python's. Sadly nether of them will take frozen feeders.