If the level of Co2 drops below 200 ppm, your plants' development will stagnate. You can fine-tune your grow room climate by adding extra Co2 for plants. To accelerate your crops' development, increase the Co2 levels up to about 1,200 ppm. Ensure optimum photosynthesis rates and improve your yields with extra Co2. You'll achieve perfect vegetative growth, kick start the blooming process and can experience up to 30% increase in yields.