20 x 20 x 1 merv 13 or fpr 10 filter.
Diy pc fan carbon filter.
Next put holes in each corner of the carbon filter square.
See the graph below that shows an example of the filter fan performance.
I used a tupperware container the same size as my fan for a make shift housing which connects my 120mm fan to a 80mm custom filter.
Form your carbon filter by setting it over the computer fan and cutting it so it barely overlaps the sides of the fan.
Supplies you need to make your own.
Make sure your fan is an one exhaust fan with at lea.
Otherwise the whole purpose of the filter will be ruined.
The flanges are must to be of the exact diameter as the ducting and inline fan.
This is the cheap way i know it looks shitty now but wait till its done and your plants are flourishing.
20 x 20 box fan.
I know everyone says to use the fan to pull out the air rather than push but i found that because pc fans are pretty low pressure i only had luck pushing.
Learn more on carbon filters their types and functions here.
Diy carbon filter for grow room.
1 x cut to fit carbon pad for air purifiers.
Your total cost for a diy box fan filter can be as low as 40 50 00 including incidentals like duct tape or higher depending on the filter options.
It still struggles a tiny bit but the back pressure makes.
Insofar as filter changing costs you will find that it is still much cheaper to buy furnace filters and variants of them without sacrificing on quality or air cleaning capacity.
I used this filter.
What items do you need.