Fresh Air Intake filteration

We are just about done construction a new grow room in our shed. It will be sealed off from the other portion where we store lawn/yard equipment etc.

We will have an exhaust fan to take out any heat n humidity but also a fresh air intake fan. What do you suggest as a filter to keep mold, bugs, pollen, dust etc from being sucked into the grow room.

We don't want to have it come from the other side of the shed because of all the lawn stuff in there. Or, would a good filter not allow any contaminants in?

thanks

shannon

Reusable, 3M air conditioner filter. It's blue and located by the A.C. filter stuff at Lowe's. You can cut it to shape and bend it. Stack sheets of it for more filtration.


You don't want dust and dirt stuck to your plants and bud. Plus the crap also clogs the blower.

SouthCross said:

Reusable, 3M air conditioner filter. It's blue and located by the A.C. filter stuff at Lowe's. You can cut it to shape and bend it. Stack sheets of it for more filtration.


You don't want dust and dirt stuck to your plants and bud. Plus the crap also clogs the blower.

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thanks.
we were thinking something along those same lines. just looking for ideas etc.

take care
shann

What sort of square footage/dimensions are you working with? What type of climate are you in?

You might want to look into a HEPA filter rated to handle your fans cfm output. Even they let a fair amount of spores/pathogens through, but are excellent at filtering particulates out, and can last quite a while when equipped with a a good pre-filter. The next step up would be channeling the fresh air through a germicidal UV-C plenum with a downstream HEPA filter.

i use six inch hepa filters, one exhaust and one intake straight to outside air in 60 sq ft outdoor shed.

two 440 cfm inline fans,

problem is that the hepa filters reduce fan airflow probably by 60% or more. i need a filter for bugs that allows more airflow.

Phresh filters makes intake filters that do what your asking, there is also the mushroom style horti-control filters. I’ve used both and both did there job.

I believe it’s called the “dust shroom”. Fits flexible duct.

newgrow16 said:

i use six inch hepa filters, one exhaust and one intake straight to outside air in 60 sq ft outdoor shed.

two 440 cfm inline fans,

problem is that the hepa filters reduce fan airflow probably by 60% or more. i need a filter for bugs that allows more airflow.

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That's the problem with HEPA filters. Very restrictive so you need triple or more surface area to get the airflow you would without filtration.

To get that and have filtered air get through a hole into a tent or grow room make a box that can be sealed to the inlet and cover 3 or 4 of the available sides with Hepa filter so you can have 100s of square inches of filter surface. A simple frame of 2x2 with mosquito screen stapled in place to support the HEPA filters. Or just a cardboard box and duct tape would do. I bought some big HEPA vacuum bags and cut them up to size. Pretty big sheet of filter paper when opened up. Fuzzy side out!

With a passive intake you should have at least double the surface area as your exhaust so a 6" exhaust is diameter^2 x .7854. That's 36 x .7854 = 28.3 square inches. Double that for 56.6 for min intake opening. Outside of that opening is your box. If sitting on the floor there are 4 sides available to have filters on so a small box say a foot square would have nearly 4 square feet of available space and one square foot is 144 square inches so there's way more than enough room to have HEPA with more than enough air flow and no need for an intake fan. The box could be inside the grow space too.

The stuff I'm using now is anti-static wipes behind some soffit vents that let air into my room from the basement. Nice and cool in the basement even in the summer so it's like free A/C.

For people that are cash strapped and desperate, nylon Panty Hose can be used as a filter. Just stretch it over the intake until you get the desired intake flow and tape it there. Several filers can be made from one pair of nylon stockings

For something more permanent, I'd go with the big filters from a forced air furnace and construct a box for it, providing it's not a micro-grow.

To save money I strap black air conditioner replacement filter foam over the end of my intake fan.

Available online or Home Depot type stores. Comes in rectangular black sheets and is easily cut to fit. And washable or vacuum clean.



I need new filter foam. Lol

AKgrower29 said:

Phresh filters makes intake filters that do what your asking, there is also the mushroom style horti-control filters. I’ve used both and both did there job.

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Well i tried panty hose and that was a bust, just bought the dust shroom to help with airflow.

MichiganMedGrower said:

To save money I strap black air conditioner replacement filter foam over the end of my intake fan.

Available online or Home Depot type stores. Comes in rectangular black sheets and is easily cut to fit. And washable or vacuum clean.

View attachment 4120788

I need new filter foam. Lol

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Great idea!