Max out on almost all other growing factors and eliminated major growing problems to see the biggest benefit from adding CO2. I’d like to point out that there are many free ways to increase your marijuana yields, such as plant training techniques, and mastering these first may even be more effective in increasing your yields than adding CO2. Before you consider CO2, you should eliminate any plant problems from your grow. I’d say that the number one way to increase your yields is to prevent plant problems. If you’re suffering from plant problems like too much nitrogen or nutrient deficiencies, you should start here when considering how to increase yields, since these will negatively affect your yields much more than any benefit you get from CO2.
Your plants can only grow as much as allowed by the lowest limiting factor, and often that factor is something else besides CO2. Yet if you have already perfected the other factors of your grow, then adding the right amount of CO2 has been shown to increase overall vegetative growth by up to 20%. If you’ve maxed out your limiting factors and sealed your grow room, than adding CO2 could be the final piece to take your grow to the next level, providing you with quicker harvests, bigger plants and enhanced yields. If you’re considering CO2 injection, ask yourself… Have I already maxed out the amount of light my cannabis plants can use with my current grow lights? (at least 7500-10000 lumens per sq foot, usually only possible with a 600W or 1000W HID light, or a few 400W HID lights close together) Have I already eliminated all problems from my grow such as nutrient problems, bugs, etc? Have I already mastered (easy and free) growth control methods to increase my yields? If I want to supply CO2 levels up to 1500 PPM, am I willing to seal up my grow area so it’s airtight? Can I maintain temperatures between 85°F (30°C) and 95°F (35°C) in my grow area?
Can I keep humidity below 70% in vegetative and 60% in flowering in my sealed room while running CO2? If your answer is “Yes” to all those questions, than CO2 enrichment may be a great choice for you and your garden! How To Get Started With a CO2 Generator or Compressed CO2. “The yeast or whatever they are methods are pretty pointless. I've noticed larger yields, more heat tolerant plants, and sooner harvest times. I burn propane but I've used tanks for years prior. So you’re ready to add CO2 to your cannabis grow room? These are the two methods used by commercial and pro growers who are serious about CO2 injection. Ability to have fine control over PPM in room using a regulator or controller. Can be automated with a controller, so relatively automatic once everything is set up. Compressed CO2 usually comes in metal containers that are under high pressure. It’s often cheaper to buy compressed CO2 from a welding supply store as opposed to a gardening or hydroponic store. The most expensive part about adding CO2 to your grow room with compressed CO2 is the initial investment in parts. After that it's pretty cheap to refill your CO2 tanks. While it is expensive to get everything up front, a single tank of compressed CO2 could last several grows by itself, and refills are cheap when you find the right place. If you have an automatic CO2 PPM monitoring system, it's simple to maintain the CO2 levels that you want. If all you have is a compressed CO2 with a regulator and timer, you'll want to inject the room with CO2 for small periods of time while the lights are on, using your timer. You may have to measure the PPM of CO2 over time and keep adjusting how much CO2 is released until you figure out how to maintain a CO2 PPM between 1200-1500 PPM. The nice CO2 tanks can be hooked up to a meter (a CO2 PPM meter) that measures how much CO2 is in the air and adjusts your CO2 output as needed. For plant growth, you want your CO2 to be between 1200-1500 PPM. The meter is attached to your CO2 tank, and it will start injecting more CO2 into the air above your plants when CO2 levels drop below the optimum. Bottled CO2 can be purchased at many hydroponic or welding stores.
These can come with a regulator/flow meter which you will need to adjust in order to output the correct amount of CO2. To use this method of enriching CO2, you will need some special equipment: 1. Compressed CO2 (available at local welding supply stores, as well as some hydroponic stores) 2. Pressure regulator, Flow Meter and Solenoid valve 3. Either a CO2 PPM monitor / controller or a regulator with timer 4. Connecting tubing, fittings and adapters (usually comes with your set) Watch a Youtube video showing the right way to use compressed CO2: Option 2: CO2 Generator. A CO2 generator burns propane, natural gas or occasionally denatured alcohol. This creates a chemical reaction that produces CO2 + water vapor. Many of these can be hooked up to a monitor for no-worries, automatic CO2 enrichment. Generates CO2 by burning propane, denatured alcohol, or natural gas.
The cheaper methods of producing CO2 this way (such as a bunsen burner) use an open flame, which is a terrible fire hazard, especially considering you are keeping temperatures above 85°F (30°C) when flooding your grow area with extra CO2. Because of the hot temperature and the electrical equipment and water that are already in your grow area, I highly recommend NOT adding a cheap CO2 burner into your grow room and risking a fire. However, more advanced CO2 generators have been specifically built for gardening applications, and these are a much better choice for a gardener as they’re built with many safety features.