HEPA filters and dust filters are straightforward means to keeping particulate matter, dust, pests, and fungal spores out of your grow tent. With a positive pressure intake attached to either of these style filters, grow tents are able to push bugs out with airflow when the attempt …to gain access to your precious plants. HEPA filters reduce incoming matter by over 99.99%, keeping your garden free of otherwise damaging molds and mildews. HTG Supply duct and HEPA filters range from 4? to 12? in size to meet the requirements of the closet gardener up to the professional facility.