The Use Of CO2 In The Frog Hobby
There are several avenues or areas that we could use CO2 in our hobby.- Killing bugs and slugs in new plants before they are introduced to a tank.
- Killing bugs and slugs in existing tanks. You might need to gas a tank several times in order to get rid of them because their eggs are very resistant to the oxygen deprivation or hypoxia.
- During the process of photosynthesis plants use atmospheric carbon dioxide to make the sugars that they need to build cellular tissue. Higher levels of CO2 seem to stimulate higher rates of photosynthesis and therefore higher growth rates. Therefore if you have a plant that is not doing well, giving it a boost in CO2 during the day-time hours may help to bring the plant back.
- According to the American Veterinary Medical Association CO2 is considered to be an appropriate and humane way to euthanize a sick or dying frog. (Edit by mod in 2020: this has changed. Read thread replies below.)
- While not frog related, you can carbonate your own beverages and you can be the life of the party with some of the dry ice tricks that I will share later.
I think that having the ability to easily and consistently generate CO2 would be of great benefit to us in the hobby so I began to so some research and then developed this article. Let’s looks at some of the options available on how to produce CO2.
This article will cover these different methods of producing CO2
- Dry Ice
- CO2 Chemical Generation
- How to Build and Operate a CO2 Generator
- Ways to Test for CO2 levels
- Using compressed CO2 Tanks
- Paintball Tanks (reusable)
- Bike Cylinders (non-reusable)
- Euthanasia Tank
- Simple Moss and Plant CO2 Chambers
Methods of Producing
Carbon Dioxide or CO2 Gas
Carbon Dioxide or CO2 Gas
1. Dry Ice CO2 Production
Most of us are familiar with using dry ice to generate CO2 gas. Dry Ice is frozen carbon dioxide. When it is warmed up, it goes directly from being a solid icy form to being a gas with no liquid stage in between, hence the name dry ice. So in order to generate the gaseous form of carbon dioxide, all we have to do is warm up a little dry ice. But dry ice has some drawbacks.
- Dry Ice is cold, extremely cold. In its frozen or solid state its temperature comes in at a nippy -78.5 degrees C or -109.3 degrees F. This extreme temperature can quickly damage plants, people and critters. If you bump or poke dry ice, it just feels super cold but you aren’t likely to suffer frostbite or skin damage. If you try and hold it or if it comes into contact with your skin for more than the briefest instant, the skin cells will freeze and you will feel a really nasty burning sensation. So if you work with dry ice always wear gloves, a long shirt, and safety glasses. I cringe when I see some of the idiots on youtube holding or chewing or chipping and breaking up dry ice without safety glasses. Holding it in your teeth can freeze the enamel of your teeth making your teeth brittle. If you need to break up dry ice, cover it with a towel as you break it up. Personally I think some of these guys on youtube are industrial strength stupid.
- If you seal dry ice in an airtight non-vented container with the lid on too tightly, the container becomes a high-pressure bomb.
- If dry ice comes in direct contact with the glass of your tank, the glass is likely to shatter due to the extreme and quick temperature changes. Metal does sing quite nicely though when it is placed in contact with dry ice.
- Although dry ice / carbon dioxide is not toxic in and of itself, the use of dry ice may create respiratory hazards for you and your animals. This is because carbon dioxide is heavier than the surrounding air that we breathe. Thus CO2 will fall down and displace all of the oxygen in any container thus creating a deadly hypoxic environment (lacking oxygen). Thus one should use CO2 only in well-ventilated areas.
- While this hypoxic environment is fine for killing bugs and slugs, dry ice is not considered a proper or humane way of euthanizing an animal. There are several reasons for this.
- a. The ultra-cold CO2 gas can cause the animal stress due to cold shock and frostbite.
- b. Animals can potentially be exposed to cold flesh burns and frostbite if they are incorrectly placed in the same tank as the dry ice and come into direct contact with the dry ice.
- c. Co2 flow rates going into the euthanasia chamber should be regulated fairly precisely, which is something that is not easily done with CO2 produced by dry ice.
Marty posted one of the best articles that I have seen with excellent photos of the process of how to safely use dry ice to rid a tank of pests.
Eliminating Vivarium Pests - Geckos Unlimited
I believe the key to using the dry ice method successfully and safely is to use hot water to initiate and activate the CO2 release. If you use enough hot water, it will raise the temperature of the CO2 gas enough so that you don’t toast your plants while you attempt to fry the bugs.
Dry Ice For Fun
I added these videos of a couple of interesting and cool things that you can do with dry ice. While it is not frog related, it is just plain fun all the same and we all need a little of that now and then.
2. Making a chemical CO2 Generator
Now if you wanted to go the least expensive route for generating CO2, you should build a CO2 generator.
A. Yeast / Sugar Generator:
The aquarium hobby uses a generator that uses yeast and sugar to create the CO2 but this type of generator is not likely to work well for us, except in a few instances where you want a long term slow generation of CO2 for plant growth / health or to generate an extended period of CO2 exposure for those really pesky pests that can handle some oxygen deprivation for a period of time.
Do-It-Yourself Carbon Dioxide Injection
This generator works by using yeast that digests the sugars in a breeding medium. One of the by products is CO2.
The Problems With Yeast / Sugar CO2 Production Systems
There are several problems with a system like this. This setup is designed to produce a steady but low volume of CO2 and when the system is first set up not a lot of CO2 is produced. It takes time for the yeast to ramp up production, to digest the sugars and to reproduce which means that the CO2 production ramps up slowly.
The other problem is that the yeast might not produce enough CO2 to displace all of the oxygen that we are trying to oust from the tank. Also as long as the lights are on, any plants that are in the tank will be metabolizing as much of the CO2 as they can.
Typically what we need in our hobby is a method for creating a lot of CO2 in a short period of time. I list it here because there are a few instances that this might be of benefit to us. (More on this later)
B. Vinegar & Baking Soda Generator:
This seems to be a much better method of creating CO2 for our hobby.
If you have ever mixed vinegar and baking soda together and seen all the bubbles produced or if you have mixed baking soda and water and poured it over your car’s battery in order to clean the battery terminals you have seen all kinds of CO2 gas bubbles being generated by this mixture of chemicals.
Here is a video of the CO2 Generator that I built and of the procedures that I use to generate the CO2. This tank has had a good slug infestation that the various nightly lettuce raids were not making a dent in their population. They came in on one plant that I had recently purchased. If I had treated this one plant by itself with CO2 it would have saved me a lot of time and trouble.
Video of the Generator in Operation
The Baking Soda / Vinegar Reaction:
When you mix an acid, in our case vinegar, which is a 5% acetic acid, with Baking Soda, also known as Sodium Bicarbonate (NaHCO3). A chemical reaction takes place as they are mixed that generates carbon dioxide gas (CO2) and water as bi-products. The reaction between baking soda and vinegar is actually two reactions, an acid base reaction followed by a decomposition reaction. They just take place extremely quickly in rapid succession.
The Ratios: Vinegar / Baking Soda
While researching the proper ratios of Venegar & Baking Soda, I found conflicting data on what the proper amounts of Baking Soda and Vinegar were to mix to together to get a balanced reaction.
Therefore, I checked with the folks on one of the science forums I belong to, Science Forum - Scientific Discussion and Debate
I asked the Chemistry folks if they would calculate the proper amounts of Baking Soda and Vinegar needed to generate a gallon of CO2 gas.
The reaction is as follows:
NaHCO3 (aq) + CH3COOH (aq) ......> CO2 (g) + H2O (l) + CH3COONa (aq)
Thus: 84gmw 60gmw 22.4L gas (i mole)
THE APROX CALCULATIONS ARE:
- Because Vinegar is only 5% acetic acid - 200ml of vinegar has about 10 grams of acid or 16.6% of a mole of acetic acid.
- We need 16.6% of a mole of baking soda which is 13.9 grams.
- Thus you would get 16.6 % of a mole of gas or 3.7 Liters of CO2 gas which equals about .97 gallons of gas
For all you purists I know these calculations are approximated but they are close enough.
Therefore you need 14 Grams of Baking Soda mixed with 200 ml of Vinegar which then produces 1 Gallon of Co2
From this I generated the following Table along with the Kitchen equivalent measurements:
CO2 Ingredients Table:
………………… Baking Soda ……………………|………………………………………… Vinegar ……………………………………………|… CO2 Output …
……14 gr =…………………3 t.……………………|…200 ml = ……7/8 c. = ………6.76 fl oz……………………|…… 1 Gallon
……28 gr =……………… 6 t. = 2 T. |…400 ml = 1 2/3 c. = ……14.53 fl oz……………………|…… 2 Gallons
……70 gr =……………1/4 c. + 3 T. | 1 L =……… 4 1/4 c. = ……33.81 fl oz …………………|…… 5 Gallons
…140 gr =………1/2 c. + 3.4 t. | 2 L =……… 8 1/2 c. = … 67.62 fl oz …………………|… 10 Gallons
…280 gr = 1 1/8 c. + 4.8 t. | 4 L = 1 gal. + …… 7/8 c. = 135.25 fl oz …|… 20 Gallons
…420 gr =…1 3/4 c. + 4.2 t. | 6 L = 1 gal. + …8 1/3 c. = 202.88 fl oz …|… 30 Gallons
…560 gr = 2 3/8 c. + 3.6 t. | 8 L = 2 gal. + …1 7/8 c. = 270.51 fl oz …|… 40 Gallons
…700 gr =………… 3 c. + 3.0 t. |10 L = 2 gal. + 10 1/3 c. = 338.14 fl oz …|… 50 Gallons
1400 gr = 6 1/8 c. ………………………|20 L = 5 gal. + …4 1/2 c. = 676.28 fl oz …|…100 Gallons
Key to Abbreviations:
Teaspoon …… Tablespoon … Fluid Ounces … Cup … Pint … Quart … Gallon …… Gram … Liter
t. = tsp. … T. = tbsp. ……… fl oz ………………… c. …… pt. …… qt. ……… gal. …… g. = gr … L …
Liquid (Fluid or Volume)
(Measurements are Approximates)
(Measurements are Approximates)
… Volume …|…… Fluid Ounce …|……………… US Equivalent ………………|… Metric Equivalent …
1 t. ……………|…………………………………………|……………… 1/3 T. …………………………………|………… 5 ml
1 T. ……………|……… 1/2 fl oz………|…………………… 3 t. …………………………………|……… 15 ml = 15 cc
2 T. ……………|…………… 1 fl oz ……|……… 1/8 c. = 6 t. ………………………|……… 30 ml = 30 cc
1/8 c. ………|…………… 1 fl oz ……|…………… 2 T. = 6 t. ………………………|……… 30 ml = 30 cc
1/4 c. ………|…………… 2 fl oz ……|…………………… 4 T. …………………………………|……… 59 ml
1/3 c. ………|… 2 2/3 fl oz ……|…………………… 5 T. + 1 t. ………………|……… 79 ml
1/2 c. ………|…………… 4 fl oz ……|…………………… 8 T. …………………………………|…… 118 ml
2/3 c. ………|… 5 1/3 fl oz ……|………………… 10 T. + 2 t. ………………|…… 158 ml
3/4 c. ………|…………… 6 fl oz ……|………………… 12 T. …………………………………|…… 177 ml
7/8 c. ………|…………… 7 fl oz ……|………………… 14 T. …………………………………|…… 207 ml
… 1 c. ………|…………… 8 fl oz ……|……… 16 T. = 1/2 pt. …………………|…… 237 ml
… 2 c. ………|………… 16 fl oz ……|……… 32 T. = … 1 pt. …………………|…… 473 ml
… 4 c. ………|………… 32 fl oz ……|……… 2 pt. = 1 qt. ………………………|………946 ml
1 pint ………|………… 16 fl oz ……|……… 32 T. = 2 c. …………………………|…… 473 ml
2 pints ……|………… 32 fl oz ……|………… 4 c. = 1 qt. ………………………|…… 946 ml = 0.946 L
8 pints ……|……… 128 fl oz ……|……… 4 qt. = 1 gal. ……………………|… 3785 ml = 3.780 L
4 quarts …|……… 128 fl oz ……|……… 8 pt. = 1 gal. ……………………|… 3785 ml = 3.780 L
1 liter ……|……… 1.057 qt. ……| 2.11 pt. = .026 gal. ……………|… 1000 ml
1 gallon …|…………128 fl oz ……|……… 16 c. = 8 pt. = 4 qt. …|… 3785 ml = 3.780 L
Dry (Weight) Measurements
(Measurements are Approximates)
(Measurements are Approximates)
1 ounce ……………………………………………………………………………………………………………… 30 grams (28.35 grams actual)
2 ounces …………………………………………………………………………………………………………… 55 grams
3 ounces …………………………………………………………………………………………………………… 85 grams
4 ounces ……………………………… 1/4 pound …………………………………………… 125 grams
8 ounces ……………………………… 1/2 pound …………………………………………… 240 grams
12 ounces ……………………………… 1/4 pound ………………………………………… 375 grams
16 ounces ……………………………… 1.0 pound ………………………………………… 454 grams
32 ounces ……………………………… 2.0 pounds ……………………………………… 907 grams
1 kilogram …………………………… 2.2 pounds = 35.2 oz. ……… 1000 grams
A note about kitchen measurements:
Not all tablespoons are the same. The Australian tablespoon is 20 ml; the British tablespoon is 17.7 ml. In most Canadian recipes, the tablespoon is 15 ml., while the American tablespoon is 14.2 ml.
In British, Australian and sometimes Canadian recipes, the "imperial pint" is used which is 20 fluid ounces. American and sometimes Canadian recipes use the American pint of 16 fluid ounces.