Ventilation and Environment Control

Controlling your grow room ventilation and environment is the most important factor in a successful indoor grow. Temperature, humidity, CO2 and airflow directly determine how efficiently your plants photosynthesise, how well nutrients are absorbed, and how effectively diseases are kept at bay. At The Horticulture Company, we stock a complete range of ventilation and environmental control equipment to keep your grow room dialled in year-round.
Extraction Fans, Inline Fans and Carbon Filters
Every grow room needs an active extraction system. Hot, humid air must be removed and replaced with fresh, CO2-rich air. We stock a wide range of inline extraction fans matched with appropriately sized carbon filters to control odour. As a rule, your extraction fan should replace the air volume of your grow space every one to three minutes. For a 1.2m × 1.2m × 2m tent, you need at least 100–150 m³/hr of extraction capacity.
Match your carbon filter diameter and rating to your fan. Carbon filters need periodic replacement — most quality filters last 12–18 months under continuous use. We stock replacement filters and pre-filter sleeves to extend the life of your setup.
Circulation Fans and Airflow Management
Extraction alone is not sufficient. Internal circulation fans strengthen stems through oscillation, prevent hot and cold spots, and reduce humidity pockets that encourage mould. Position at least one fan at canopy height and one near the floor. In larger rooms, consider clip fans, wall-mounted fans and duct booster fans to ensure total air movement throughout the space.
Good airflow also helps maintain a healthy VPD (Vapour Pressure Deficit). Keep VPD between 0.8 and 1.2 kPa in vegetative growth and 1.0 to 1.5 kPa in flowering for optimal nutrient uptake and vigorous growth.
Temperature and Humidity Controllers
Manual timers and fan speed controllers give basic control, but digital environmental controllers offer precise, automated management. Our range includes dedicated fan speed controllers, combined temperature and humidity controllers, and smart controllers that integrate with multiple devices simultaneously.
We have been helping growers set up effective ventilation systems since 2017. Our team can advise on correct equipment sizing for your specific grow space. A well-matched ventilation system is quieter, more energy-efficient and far more effective than an oversized system running at low speed.
CO2 Enrichment and Air Quality
Ambient CO2 is approximately 400 ppm. Enriching your growing environment to 1000–1500 ppm can increase growth rates by up to 30% under high light intensities. We stock CO2 controllers, burners, bags and canisters for every setup size. Our ventilation range also includes silencers for noise reduction, ducting and fittings, humidity controllers, and dehumidifiers for large grows. Browse the full range below.