Setting up Air Filters in your Grow Room

Emporium Hydroponics • February 11, 2026

There are different filters for different purposes....

Using air filters in a hydroponic grow room is mainly about odour control, air cleanliness, and pathogen prevention. Since hydro systems rely heavily on clean, controlled environments, proper filtration makes a big difference in plant health and discretion.

Using air filters in a hydroponic grow room is mainly about odour control, air cleanliness, and pathogen prevention. Since hydro systems rely heavily on clean, controlled environments, proper filtration makes a big difference in plant health and discretion.

Here’s a clear breakdown of how to use them correctly:

Carbon Filters (Odour Control) remove smell (especially during flowering stage) and arebest for strong-smelling plants

Types of Air Filters You’ll Use

Carbon Filters (Odour Control)


Purpose: Removes smell (especially during flowering stage).
Best for: Strong-smelling plants

How to use:

  • Attach carbon filter to an inline exhaust fan
  • Mount it at the top of the grow room/tent (hot air rises)
  • Airflow direction: Filter → Fan → Duct → Outside


Pro Tip:
Always match the filter CFM rating to your fan’s CFM.

HEPA Filters (Air Cleanliness & Pathogen Control)

Purpose: Removes...

  • Mould spores
  • Powdery mildew
  • Pollen
  • Dust
  • Insect particles


How to use:

  • Place near air intake or inside the room
  • Best paired with positive pressure systems
  • Run continuously in humid environments


Especially important in hydroponics because high humidity risks getting mould.

Intake Pre-Filters (Dust & Pest Prevention)

Purpose: Stops:


  • Bugs
  • Dust
  • Outdoor contaminants

How to use:


  • Install on passive intake vents
  • Or attach to intake ducting
  • Clean weekly

Basic Airflow Setup for Hydroponics

Fresh Air Intake (Filtered) → Grow Room → Carbon Filter → Inline Fan → Exhaust Outside


Target Air Exchange Rate:


  • Replace room air every 1–3 minutes
  • Calculate CFM needed:


Room Volume (L×W×H) ÷ 1–3 minutes = Required CFM


Placement Tips


✅ Carbon filter high up
✅ Intake low (cool air enters from bottom)
✅ Keep ducting short and straight
✅ Seal all light leaks
✅ Maintain slight negative pressure (walls suck inward slightly)


Negative pressure ensures odours don’t leak out.

Filter Type Replace / Clean
Carbon Every 12–24 months
HEPA 6–12 months
Pre-filter sleeves Wash every 2–4 weeks

Maintenance Schedule

If you smell odour it means the carbon filter is saturated.

Extra Tips for Hydroponic Rooms

  • Keep humidity levels at 40-60% duting the veg stage and 40-50% when flowering
  • Use oscillating fans for internal airflow
  • Combine filters with dehumidifier in high humidity
  • Seal cracks to prevent unfiltered air leaks