18x24x4 (3 5/8) Pleated Air Filters MERV 15 Plus Carbon 6 Pack botanicare retain water and work well

retain water and work well for bottom watering

single pocket

Dosatron Water Powered Doser 40 GPM 1:3000 to 1:800 - 1-1/2 in Kit (D8RE3000VFBPHY)

Since you can't return custom sized air filters

the Grower’s Toolbox is a complete simple crop management system that helps you get it right

18x24x4 (3 5/8) Pleated Air Filters MERV 15 Plus Carbon 6 Pack botanicare retain water and work wellNordic Pure 18x24x4 MERV 15 Plus Carbon air filters are made of electrostatically charged synthetic materials with an added flat panel infused with activated charcoal that will attract and capture most airborne particulates in your home. 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 while