12_1/2x23_1/2x1 MERV 13 Plus Carbon AC Furnace Filters 6 Pack dupe low-nitrogen formula supports strong

low-nitrogen formula supports strong

Numbers of control channels- 3

Please note that this product will increase the PPM (parts per million) of your nutrient solution

a jar test is highly recommended before applying this product

In the weeks before the flushing the dose can be increased to 4ml per litre water

12_1/2x23_1/2x1 MERV 13 Plus Carbon AC Furnace Filters 6 Pack dupe low-nitrogen formula supports strongNordic Pure Custom MERV 13 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