Intake air filter

Looking for ideas for intake air filters? I will be running 2 4” booster fans for intakes in a 4x8 room with a 8” exhaust.

I will be mounting the booster fans directly onto the wall with ducting running to ground level.

I’d like to filter out as much stuff as possible like dust, small pests, cat hair etc....

Dust Shrooms are what I use for my intakes. They are outdoors. Very durable, washable. They stop pollen, bugs, spores.

They sell a cleaning kit, it has an oil that you spray on the cleaned dust shroom (it comes with some already on it). This grabs anything that tries to get thru. Very effective. I wash my smaller 10" one in the washing machine, my bigger 12" one doesn't fit so I clean it in the tub. Mine are both outside in basement window wells so they are tough. I clean mine about 2x a year because they are outdoors. Indoors they probably wont need cleaning for much longer time.

Also if you aren't worried about pollen or super fine particles and the filter is indoors, you can use an old tee shirt and cut a piece out and using a proper size hose clamp just put it on the end of a piece of galvanized duct. If you want extra filtration you can just mist it on the outside with some vegetable oil.

I will look into those now thanks.

Renfro said:

Also if you aren't worried about pollen or super fine particles and the filter is indoors, you can use an old tee shirt and cut a piece out and using a proper size hose clamp just put it on the end of a piece of galvanized duct. If you want extra filtration you can just mist it on the outside with some vegetable oil.

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Yeah I was just more concerned about like cat hair and bigger particles.

bk78 said:

Yeah I was just more concerned about like cat hair and bigger particles.

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Yeah then go with the cheap option. I used to run air cooled 8" hoods. I did the tee shirt trick on those to keep dust out of my lights. Worked great. You could see the dust buildup after a run. Easy to change, washable or just cut a new piece.

Renfro said:

Yeah then go with the cheap option. I used to run air cooled 8" hoods. I did the tee shirt trick on those to keep dust out of my lights. Worked great. You could see the dust buildup after a run. Easy to change, washable or just cut a new piece.

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You think I should go with a 4” intake on each side of the room with the 8” exhaust? Or should I just go with a single 6” intake on the opposite side the exhaust is on? I will be moving the door to the middle as well. I have about 3 weeks left until I harvest them I plan on building this

bk78 said:

You think I should go with a 4” intake on each side of the room with the 8” exhaust? Or should I just go with a single 6” intake on the opposite side the exhaust is on? I will be moving the door to the middle as well. I have about 3 weeks left until I harvest them I plan on building thisView attachment 4284182

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Assuming the exhaust fan is a good centrifugal blower I would run just the 8" exhaust up high with a passive intake down low on the opposite side of the room. The area of the passive intake should be about 113.5 square inches of area (2x the 8" exhaust area of 56.75 square inches).

The booster fans are more of a restriction than anything IMO. The area of two 4" rounds is only 25 square inches total, so even if you had two centrifugal 4" blowers thats not equal to the exhaust and thus restrictive.

If you wanted to do a push pull then I would recommend matching 8" blowers on each end of the room, intake low and exhaust high. As little ducting as possible as thats a restriction.

Renfro said:

Assuming the exhaust fan is a good centrifugal blower I would run just the 8" exhaust up high with a passive intake down low on the opposite side of the room. The area of the passive intake should be about 113.5 square inches of area (2x the 8" exhaust area of 56.75 square inches).

The booster fans are more of a restriction than anything IMO. The area of two 4" rounds is only 25 square inches total, so even if you had two centrifugal 4" blowers thats not equal to the exhaust and thus restrictive.

If you wanted to do a push pull then I would recommend matching 8" blowers on each end of the room, intake low and exhaust high. As little ducting as possible as thats a restriction.

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Yeah I’m just trying to save as much space as possible as well as trying to limit as much light leaks as well. I will be in the lung room during lights off so I was trying to limit the potential of light getting into the flower room.

You could probably cobble together a nice light trap with some cardboard. Make the inside black and not reflective. I drew up a little possibility for ya. As long as the opening on the outside isn't in direct lighting it should work.

Renfro said:

Dust Shrooms are what I use for my intakes. They are outdoors. Very durable, washable. They stop pollen, bugs, spores.

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So I went with a dust shroom quick question though. Can they be run with air blown through them instead of sucked through them? I was planning on using a pre filter outside of my room like this https://hydro-lite.com/products/bug-screen-1

Then put the dust shroom inside my room attached to my blower?

bk78 said:

So I went with a dust shroom quick question though. Can they be run with air blown through them instead of sucked through them? I was planning on using a pre filter outside of my room like this https://hydro-lite.com/products/bug-screen-1

Then put the dust shroom inside my room attached to my blower?

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I suppose you could use the dust shroom that way, shouldn't need the bug screen though, that dust shroom will do the job. Mine run outside in basement window wells and they are filtering out bugs just fine lol.

Dust shrooms are great but they are expensive. All ready made intake filters are SO expensive. I made my own killer intake filter like this.

I bought an 8" x 8" to 6" square to round register from Home Depot for $12,
https://www.homedepot.com/p/Master-Flow-8-in-x-8-in-to-6-in-Ceiling-Register-Box-CRB8X8X6/203612870

then bought a hepa furnace filter to size, 8" x 8" and put it in.
https://www.airfiltersdelivered.com/8-x-8-x-1-premium-merv-8-pleated-air-filter.html?qty=1&gclid=Cj0KCQjwnpXmBRDUARIsAEo71tSK7fkdromcy06u9Gup2BXXYpGldkyZrdOiq6HhIGS6etaXIFEyJEAaAoLIEALw_wcB


You can even add an 8 x 8 register vent to it from Amazon for $9 to make it look pretty.
https://www.amazon.com/Steel-Return-Air-Grilles-Dimensions/dp/B01HYPU2XI/ref=pd_srecs_sabr_st_of_17?_encoding=UTF8&pd_rd_i=B01HYPU2XI&pd_rd_r=360e7e19-523e-11e9-a585-0fccb0784f1b&pd_rd_w=7Jpik&pd_rd_wg=HkTmJ&pf_rd_p=1c3a4e98-860b-4238-ad94-e16cdcd7cb20&pf_rd_r=4153FWZ544S9Q8RE2B1N&psc=1&refRID=9AF56VK4FG86FMS0FZ50


Comes to $36 total. This way you can also choose the degree of filtration you want.

bk78 said:

Looking for ideas for intake air filters? I will be running 2 4” booster fans for intakes in a 4x8 room with a 8” exhaust.

I will be mounting the booster fans directly onto the wall with ducting running to ground level.

I’d like to filter out as much stuff as possible like dust, small pests, cat hair etc....

Click to expand...

ok first off no one has asked u for the Height of the room i see u have it marked at 6 foot in that one is it the same
LxWxH= CF that is the number we need to know to do it right
now with it have a exhaust in the room too need to know the CFM rating on the filter and the fan (those 2 should match as close to possible filter and fan sucking)

what u want is a lvl 7 filter u can buy it from home depot i go lvl 10 might as well trap it all few bucks more on filters tho



DIY
u need
razor or sharp knife for cutting
1 sharpie any color
12x12x12 inch cardboard box ......get several
6 inch booster fan (metal blades cfm should be 240)
1 can of flex seal ( spray rubber)
tape measure or 1 foot ruler
4 paperclips
roll of duct tape/gorilla

it is pretty simple u take off the cardboard flaps on one side
close up the flaps on the other side (do not seal let ) take the 6 inch booster and put it in the middle trace the outline with marker and cut way with blade
then seal it up with duct tape leaving the center open but sure to get the sides and what is left
take box outside and put on a coat or 3 of the spray rubber to the inside of the box coating and sealing it all up
now on each side in the open side of the box measure 1 inch down on the sides (center mass of box) unfold the paperclips and poke tho so some metal is sticking out like a back stop
the filter goes in the side open and u just duct tape the edges to the box (cutting it when filter is dead and need replacement) they should measure 12x12x1 so the reason for the back stop makes it simpler to tape in ....after can take them out or tape them down (paperclips)


this will work with 6 inch booster fan u can
1 tape fan to box and ducting to exhaust from it (from room cool Co2 air )
2 tape the duct to the box and have fan in area sucking in
3 idea 2 but with more ducting at the end of the fan

when i did this i did the fan to the box way and had the ducting above my plants and lights dumping down in with a defuser (bathroom vent cover outdoor) on it .....it worked great in my house back in the day (guy house vacuum 2 times a year ) i was getting 215 CFMs off might when i did it 2 of them set up like that kept my area cool and slight negative pressure with a 6 inch inline fan doing 400 cfms

justugh said:

ok first off no one has asked u for the Height of the room i see u have it marked at 6 foot in that one is it the same
LxWxH= CF that is the number we need to know to do it right
now with it have a exhaust in the room too need to know the CFM rating on the filter and the fan (those 2 should match as close to possible filter and fan sucking)

what u want is a lvl 7 filter u can buy it from home depot i go lvl 10 might as well trap it all few bucks more on filters tho



DIY
u need
razor or sharp knife for cutting
1 sharpie any color
12x12x12 inch cardboard box ......get several
6 inch booster fan (metal blades cfm should be 240)
1 can of flex seal ( spray rubber)
tape measure or 1 foot ruler
4 paperclips
roll of duct tape/gorilla

it is pretty simple u take off the cardboard flaps on one side
close up the flaps on the other side (do not seal let ) take the 6 inch booster and put it in the middle trace the outline with marker and cut way with blade
then seal it up with duct tape leaving the center open but sure to get the sides and what is left
take box outside and put on a coat or 3 of the spray rubber to the inside of the box coating and sealing it all up
now on each side in the open side of the box measure 1 inch down on the sides (center mass of box) unfold the paperclips and poke tho so some metal is sticking out like a back stop
the filter goes in the side open and u just duct tape the edges to the box (cutting it when filter is dead and need replacement) they should measure 12x12x1 so the reason for the back stop makes it simpler to tape in ....after can take them out or tape them down (paperclips)


this will work with 6 inch booster fan u can
1 tape fan to box and ducting to exhaust from it (from room cool Co2 air )
2 tape the duct to the box and have fan in area sucking in
3 idea 2 but with more ducting at the end of the fan

when i did this i did the fan to the box way and had the ducting above my plants and lights dumping down in with a defuser (bathroom vent cover outdoor) on it .....it worked great in my house back in the day (guy house vacuum 2 times a year ) i was getting 215 CFMs off might when i did it 2 of them set up like that kept my area cool and slight negative pressure with a 6 inch inline fan doing 400 cfms

Click to expand...

Reading this post made me remember in the movie Apollo 13 when the astronauts were being told by ground control how to make a filter adapter.

I built the room 2 months ago and went with the Horti control dust shroom.

Renfro said:

Reading this post made me remember in the movie Apollo 13 when the astronauts were being told by ground control how to make a filter adapter.

Click to expand...

it works and the lvl of the filtering is all on u ......i did it becuase i lived in a split lvl house and had the grow room on the bottom floor .......the CO2 intake was a bonus and the natural cool air kept me from needing to us a AC all except summer months

bk78 said:

I built the room 2 months ago and went with the Horti control dust shroom.

View attachment 4325510

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Looks good bro. Nice work. Good choice on the dust shroom.

Renfro said:

Looks good bro. Nice work. Good choice on the dust shroom.

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Question about washing and oiling the dust shroom? Just wash by hand I take it? And what can I use to re oil the filter once dry?