The Organic Air HEPA filter has been developed using opposing dual cone technology that optimizes airflow even as it traps and filters out 90 % of molds, insects and bacteria. With the Organic Air Filter protection, your greenhouse or grow room provides just the kind of contaminant-free conditions your plants need to grow to their full potential. As HEPA filters need a large air flow, it is not recommended that you use an 8 inch filter with an 8 inch blower for instance. It would be much more beneficial to use an 8” filter with a 10” fan. HEPAs need the air flowing as fast as possible and in order to do this, you should step up the fan or blower size and use a duct reducer to attach your HEPA filter to the blower. Again, use a larger fan size than the HEPA filter size! More air equals more filtration with a HEPA.