20x22x1 Pleated MERV 12 Plus Carbon AC Furnace Filters 3 Pack spl_magfan 14'' x 40'' Charco Filters

14'' x 40'' Charco Filters Plus Activated Carbon Air Filter

and HI9811-5 portable multiparameter meters

Can be used in all growing stages

Current runs between two electrodes within the canister

The Matrix is reusable and can sit on top of or fit into your pot

20x22x1 Pleated MERV 12 Plus Carbon AC Furnace Filters 3 Pack spl_magfan 14'' x 40'' Charco FiltersNordic Pure 20x22x1 MERV 12 Plus Carbon air filters are made of a dual material where the MERV rated material has been fused together with a carbon layer. This results in less flow restriction and 33% more surface area for cleaner smelling air. It will help eliminate unwanted odors as well as trap most airborne dust and particulate matter for fresh, clean air. Odorous gases and vapors (VOC) are attracted to and held by the activated carbon material