Alternative Method of CO2 Production


I’m not even 24 hours into my grow and I’m already hating the yeast/sugar method of CO2 production. This got me thinking about an alternative, which was sitting in my garage. Using my kegerator tank/regulator to provide the CO2 into the chamber. I’m thinking I could set the regulator as low as it goes, probably around 1PSI, then run the line into an Arduino controlled solenoid valve, then into the chamber. Thoughts? Anyone have experience with these types of valves?


I think using a valve to regulate the flow would over-complicate things. I’ve just stuck the hose inside the chamber and set the regulator super low. I’m monitoring the CO2 levels and it looks at the minimum I can compensate for the loss of the chamber itself and keep it at a desired level. I’ll be using this method instead of the yeast/sugar method.


Hello ToeSmack,
Typically growers will just plug the regulator into either a timer, or co2 ppm meter. Kind of just depends on how precise you want to be and/or budget. How wide open the regulator should be set depends on the size (cubic feet) of the room, and number and size of the plants. To be honest I don’t know anyone who grows in such a small area and uses co2 enrichment.

CO2 Regulator

A typical lamp timer will turn on and off the regulator at preset intervals. Most lamp timers are either 15 or 30 minute minimum settings. Digital timers can give you more control on the on and off duration’s, but be careful, they may not have many total settings. So if your going to run short on cycles and frequently during the day, you may be better off with a cycle timer. Cycle timers you set the duration of the on time and the off time and it cycles indefinably on that cycle. Many cycle timers also have a photo cell so it can be set to not go on at all during dark periods.

CT-1 Short Cycle Timer
Autopilot Analog 24HR Recycling Timer

But a co2 ppm meter will be able to turn on and off the regulator to based on preset co2 ppm values. Some can also be set and controlled by temp, humidify, and/or photosynthesis period. It’s important to remember that plant co2 intake is affected by temperature and humidity levels, as well as light intensity (par/lxu) during photosynthesis. Here are a couple of videos on setting up the regulator, one using a lamp tier and the others by ppm meters.

co2 PPM Controller

Here’s just one place that sells a variety of co2 enrichment equipment,
Co2 Equipment

Here’s some information on co2 enrichment methods as well as understanding indoor climate control and how all the variables affect co2 intake.

Carbon Dioxide Enrichment Methods
Control Yourself: Understanding the Basics of Indoor Climate Control

In such a small space (cubic feet), it will be easy to over saturate with co2. co2 levels above 1,500 ppm. 2,000 ppm start to become toxic to the plants. So you will likely need to use the co2 PPM meters to regulate the co2 levels so you don’t over saturate it.


Thanks for all this great info @HomeHydro. Surely your experience in hydroponics will benefit us all greatly!


Hello ToeSmack,
Not a problem, I’m glad it was useful to you. I’ve been growing plants hydroponically for many years, but I don’t know much of anything about building electronics, writing computer codes etc…