There are several methods to generate C02 carbon dioxide enrichment for greenhouses and grow rooms. A very basic Carbon Dioxide generator can be easily made with sugar, baking soda, and dry active yeast. Other methods include Dry Ice and baking soda/vinegar.
Producing C02 with dry ice works to a very limited extent by simply allowing dry ice to melt in your grow room, it will boost the c02 levels. I freeze-dry foods with dry ice so sometimes I use this mode, it is not as reliable as other methods but it sure is cost-effective.
The most effective Do it yourself C02 generator involves the use of sugar, baking soda, and dry active yeast.
How to Make CO2 With Yeast
- Bring 3 cups of water to a steady boil then pour it into a suitable container.
- Add 2.5 cups of sugar to the water and stir vigorously then place it in the grow room.
- Mix a teaspoon of baking soda with 3 cups of cool water and add to the hot water/sugar. Yeast dies in hot water and will not activate in cold water. The best water temperature range for yeast activation is 100 – 110 F.
- Add three 1/4 oz. packs of dry yeast. Distiller’s yeast works best, it lasts longer but bakers yeast will suffice. Do not disturb the container after adding your yeast.
The yeast will feast on the sugar and emit c02 [and alcohol] as a waste product. This solution will emit co2 at a steady rate even in the night cycle when plants don’t actually use much. The alcohol will eventually kill off the yeast so the solution should be replaced with a new batch about every 2 weeks or when tiny minute bubbles stop coming to the surface of the liquid.
This system works well for a small confined grow room with several plants. For larger set ups you’ll need to add several pots of the solution strategically placed to circulate optimally throughout your greenhouse or grow room.
Vinegar and Baking Soda CO2 Generator
Another method of producing carbon dioxide, without using yeast or producing alcohol is with vinegar and baking soda. Perhaps as a kid, you made one of those bubbling vapor spewing volcanoes as a science project. Chances are it was done with vinegar and baking soda. Putting the 2 together induces a chemical reaction that generates C02.
It is short-lived but temporarily boosts carbon dioxide / C02 levels. Some growers set up a drip system that allows droplets of vinegar to gradually drip into baking soda, which releases some C02 with each subsequent droplet.
You cannot accurately control CO2 output with any of the DIY generation methods, multiple variables can cause spikes and dips in the carbon dioxide levels so it is advisable that you monitor it closely.