CO2 Pads "Green Pads" are the same as meat preservation pads.

Tapoirai

Member
I just wanted to share a bit of research I did on the topic. The content in the pad has to be food safe to use. This means you have to be able to consume it. CO2 can be produced using sodium bicarbonate and citric acid. If you use powdered citric acid and baking soda with some moisture you can produce CO2. These "Green Pads" are just meat packing pads. Once they get wet they start the reaction and CO2 is produced. CO2 is the only gas in the atmosphere that can prevent decay. So these pads are used to increase the shelf life of meat. So it turns out that many industries use this same material, floral companies, plant shippers, fish and poultry, the list goes on. Based on how much moister the pad receives will "regulate" the CO2 production.

As an experiment, take some white vinegar (contains 5% citric acid) and some baking soda, mix them to together is a glass. It'll bubble like crazy. The bubbles contain CO2. If you put this same mixture in a bottle and put the cap on... It'll explode.

I saw these in the grow shop and bought them to try and produce CO2 without buying an expensive setup. When I opened the ziplock I thought.. "Hmmm, this looks like one of those meat package pads." So I googled the meat packing pads and found the company who makes them. Then I looked up where to buy them and I found a site that sells them 2000 for $50; for the small 4" X 6" pads. The grow shop sells 10 for $14. It takes about 7-10 to get through a propagation, or so it seems. Some have claimed that in 4-5 days they had roots everywhere. The grow shop I go to showed me some tomato plants that were ready for soil in 4 days. They really work in the propagation dome.

10 grams of citric acid to 14 grams of sodium bicarbonate will produce roughly 1 gallon of CO2 gas. You can buy a whole box baking soda (1lb) for ~$1.50. You can buy 5lbs of citric acid for $16.

There are 7.5 gallons in one cubic foot. Based on some rough math it would take ~8 teaspoons per cubic foot to achieve 1500 PPM of CO2. Since most everyone uses fans in the flower room you would have to calculate your requirement based on the cubic foot of your room. CO2 is heavier than oxygen. My tent in 3 X 5 X 6.5. It will take 808 teaspoons to reach 1500 PPM. 1 gallon is 768 teaspoons. So, roughly 1 gallon will fill my room. Looking back to the calculation you'll notice you can make a hell of a lot of CO2 for ~$20.

As moisture is added to the solution the more CO2 will be generated. This is why these pads require a mist spray or high relative humidity to produce CO2.

I am sure this same company that sells 2000 for $50 has the large size pads too. I'm going to find a way to manage the reaction so I can regulate the amount of CO2 is produced using the citric acid and sodium bicarbonate process.

Just thought I'd share what I was working on.
 
nice way to try new shit i will be keeping a close eye on this since i would love to run co2 just dont have room for a huge setup or the funds right now
 

karr

Well-Known Member
Thanks for posting this! it sounds like we might finally have a cost effective alternative to bottle and burner co2.

Keep up the good work and try to find out how we can effectively control this and were on a new road.

Rep this guy!
 

Tapoirai

Member
I ordered my pure citric acid the other day so I should have it soon. I am digging out my old chemistry books to remind myself how do to the math to determine reaction rate. Anyone know off hand what the optimum mix is? I loosely calculated 10 and 14 but I'd like to measure out exactly what the precise values are.
 
Top