20x20x5 (4 3/8) Honeywell/Lennox Replacement MERV 14 Air Filters 4 Pack commercial-lighting-fixtures To use Hydrofarm's CO2 Flow

To use Hydrofarm's CO2 Flow Rate Calculator

No more truckloads of costly

The product you receive consists of whitefly pupae that have been parasitized with Eretmocerus eremicus

this fact is commonly overlooked by growers

The Humic and Fulvic acids as well as other key vitamins in the Multi Total improves nutrient transport and increases substrate fertility

20x20x5 (4 3/8) Honeywell/Lennox Replacement MERV 14 Air Filters 4 Pack commercial-lighting-fixtures To use Hydrofarm's CO2 FlowImportant Note: Almost ALL furnace filters have a different "actual size" than the nominal size printed on the air conditioner filter. It's best if you measure your air filter for the EXACT size and compare it to our "Actual Size" and then you can be sure your A C air filter fits! With the 4" and 5" air filters there is a wider variance between the nominal and actual size depending on the manufacturer. We also carry 4 7 8 and 5 1 4 inch depth filters,