Alongside light, water and nutrients, CO₂ is one of the building blocks of photosynthesis. In a closed grow tent, plants can use up the CO₂ in the air faster than fresh air replaces it. This collection contains natural CO₂ enrichment in the form of CO₂ bags in Medium and XL sizes, which release CO₂ gradually without any equipment or power. Hang the bag above the plants, as CO₂ is heavier than air and sinks down onto the canopy, and choose the size based on your tent volume. See CO₂ bags, read about grow room climate or monitor conditions with climate controllers.
Questions & answers about CO₂
All growing questions →- Climate What is the ideal temperature in a grow tent? About 22 to 28 °C with the lights on, and no more than about 5 °C cooler when they're off. Read the answer →
- Climate What is the ideal humidity in a grow tent at each stage? About 65 to 80% for seedlings and cuttings, 50 to 70% in growth, and 40 to 50% in flowering, a bit lower toward the end. Read the answer →
- Climate What is VPD and how do I use it in a grow tent? VPD (vapour pressure deficit) combines temperature and humidity into one number that tells you how strongly the air pulls water out of th... Read the answer →
- Climate Do I need a climate controller, or is a thermo-hygrometer enough? A thermo-hygrometer is enough to start with. A controller is worth it once you want fans, humidifier and heater to react on their own. Read the answer →
