7_3/4x25_3/4x1 Exact MERV 7 Plus Carbon AC Furnace Filters 6 Pack light Please Note: The AS-2 requires

Please Note: The AS-2 requires the SPH-1 for supplemental power

The optimal pH for plant growth is between 5

It features a photocell to ensure daytime only dosing of CO2 via a generator or regulator

continuously improving mix

7_3/4x25_3/4x1 Exact MERV 7 Plus Carbon AC Furnace Filters 6 Pack light Please Note: The AS-2 requiresNordic Pure Custom MERV 7 Plus Carbon air filters are made based on the actual measurements so be sure to measure your current filter to get the EXACT dimensions before ordering. As with all Nordic Pure filters, the effective life of your filter depends on the environment in which you live. We recommend changing 1 and 2 filters every 30 90 days. Our 4, 5 and 6 inch thick filters could last up to 6 months. EXACT MEASUREMENT: Furnace and air condition