What's in my exhaust?

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f0nzy

New Member
I'm looking at purchasing a perpetual harvest setup with LEDs- the Kind 1000s
one 5x5 tent for vegging, one 5x5 for drying, one 9x9 housing 24 in DWC for flowering.
I'm wondering however about the exhaust, since each of the tents will have carbon filter exhausts, is it safe to exhaust into the house or could this be a health hazard? I mean, what's in the actual exhaust? Is it best to exhaust going outside? If so I think I just added a few hundred $ to this plan
 
nomofatum

nomofatum

Well-Known Member
So you are in a cold climate and want your grow to help heat your house right? Me too. To be extra safe I added a hepa to filter everything the carbon misses. With all 3 of those going at once, I would bet some big $$$ that you will need a dehumidifier. The 9x9 may be enough to require a dehumidifier alone depending on the size of the building.

I actually have a 3rd layer in my filter system, but I'm not sure if it really does much. Lots of hunting clothing using silver ion technology to filter a hunter's scent. Well I was making up colloidal/ionic silver for use to force herm. Made a bad initial batch (more ionic less colloidal), so I dropped a bag of cotton balls in, dried them, dropped them back in dried, 4-5 times. So I had ionic silver cotton balls, I lightly packed the space between the carbon and the hepa with these cotton balls.
 
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f0nzy

New Member
Dude that is freaking genius lol!! i'm good with heat, I switched to wood stove and plan on converting to a rocket mass heater eventually. The real concern is exhausting into the house vs outside, and whether or not it's healthy in the long term to be breathing that in. Not having to add that potential layer of discoverability by exhausting outside is a good benefit, in addition to the extra heat.

So you're saying to go through a HEPA filter after the carbon exhaust?? I didn't think that was possible- how???

Speaking of HEPA filter- should I keep a small one inside the 9x9 flowering tent, to help prevent mold etc? Or would outside, in the general area around the tent work just as well?
 
nomofatum

nomofatum

Well-Known Member
f0nzy said:
Dude that is freaking genius lol!! i'm good with heat, I switched to wood stove and plan on converting to a rocket mass heater eventually. The real concern is exhausting into the house vs outside, and whether or not it's healthy in the long term to be breathing that in. Not having to add that potential layer of discoverability by exhausting outside is a good benefit, in addition to the extra heat.

So you're saying to go through a HEPA filter after the carbon exhaust?? I didn't think that was possible- how???

Speaking of HEPA filter- should I keep a small one inside the 9x9 flowering tent, to help prevent mold etc? Or would outside, in the general area around the tent work just as well?
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Go to the store find a rectangular HEPA and a rectangular activated carbon filter of the same size (or get a bigger carbon filter and cut it.) Build a box with a duct flange as the input and and open output with the filters mounted between. Parts: piece of plywood, calk, duct flange, a hepa, and a carbon filter.

Just make sure your fan is designed to push through back pressure. The fan blade kind won't cut it, you need the inline that looks like a turbine.

Just use HEPA on exhaust.

If you want a cool idea to prevent mold with an extra bonus, look at UV lighting. UV kills mold, UVB (note the B, UVA doesn't, UVC is murder for us and the plants) makes cannabis produce more resin and convert more CBD to THC.
 
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WeekendSupervisor

WeekendSupervisor

Well-Known Member
Plants fart out oxygen. I love that shit. It's totally good for you. Also, I am really jealous of your huge grow. I love it. Good luck.
 
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f0nzy

New Member
WeekendSupervisor - thanks, I guess I'm overthinking it. Probably less chemicals in the exhaust than the typical house anyway (toxic paint, formaldehyde, fiber glass etc). About the big grow, I'm sort of thinking to start smaller, or build it myself. $11k seems pretty steep now that I've compared to other builds (but then i have to factor in time and it supposedly being turn-key ready to go), so I'll need to make a decision pretty soon. 2 of the 3 potential patients I'm speaking with are seeking for the CBD heavy strains, while the other two prefer THC, so I'm back to the research phase to determine which strains I can run off the same res/nutes/schedule etc. Shouldn't be hard, I hope, but want to make sure I have everything down before going willy nilly lol. Thankfully they understand I am a newbie, but I learn quick and have demonstrated a love for all things green (I'm talkin kale, spinach, beets, microgreens etc lol).

Nomofatum - Thank you so much for sharing this wisdom! HEPA only on exhaust would be sure particulates are filtered before being exhausted into the building, I get it. But your post sparks an additional thought when I consider this design. Clean air is being exhausted, but what about air coming in? I was told not to worry much about mold spores/contaminants entering the tent, but mold is everywhere. Is there an affordable ($500 or less) HEPA filter with UVB technology out there, that I could keep in the same room? This would solve most of my mold worries :D - or would it??
 
nomofatum

nomofatum

Well-Known Member
f0nzy said:
WeekendSupervisor - thanks, I guess I'm overthinking it. Probably less chemicals in the exhaust than the typical house anyway (toxic paint, formaldehyde, fiber glass etc). About the big grow, I'm sort of thinking to start smaller, or build it myself. $11k seems pretty steep now that I've compared to other builds (but then i have to factor in time and it supposedly being turn-key ready to go), so I'll need to make a decision pretty soon. 2 of the 3 potential patients I'm speaking with are seeking for the CBD heavy strains, while the other two prefer THC, so I'm back to the research phase to determine which strains I can run off the same res/nutes/schedule etc. Shouldn't be hard, I hope, but want to make sure I have everything down before going willy nilly lol. Thankfully they understand I am a newbie, but I learn quick and have demonstrated a love for all things green (I'm talkin kale, spinach, beets, microgreens etc lol).

Nomofatum - Thank you so much for sharing this wisdom! HEPA only on exhaust would be sure particulates are filtered before being exhausted into the building, I get it. But your post sparks an additional thought when I consider this design. Clean air is being exhausted, but what about air coming in? I was told not to worry much about mold spores/contaminants entering the tent, but mold is everywhere. Is there an affordable ($500 or less) HEPA filter with UVB technology out there, that I could keep in the same room? This would solve most of my mold worries :D - or would it??
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No no no. Just use hepa filters and add UVB lighting to your tent. It will make your buds better and kill any mold spore that enters the tent. If you want crazy perfect weed you can filter incoming air too, but that is crazy anal.
 
nomofatum

nomofatum

Well-Known Member
Also, when I say hepa, were talking a replacement filter not a HEPA system, I got 2 for $30. Save the $500 for something worth it.

Just make sure you see 99.7, 99.9, or 99.97% on the package. Any of those are true HEPA, not pretend vacuum cleaner HEPA.

There are actually two cases where you want a HEPA on your intake, breeding tent, or if bringing air in from outdoors. (pollen filter)
 
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jijiandfarmgang

jijiandfarmgang

Well-Known Member
Don't go on a wild goose chase, chasing what someone says is the latest and greatest growing secret.

Forget the UVB, CO2, new generation LED lighting, magic sauce supplements or any other snake oil out there. Stick to a basic growing method.

If you want to use HEPA for intake filter, go ahead, but you really need to upsize your intake fan as they are a restriction.

Like you said mold is everywhere, forget about the HEPA fixing that, you need to keep your humidity in check.

- Jiji
 
nomofatum

nomofatum

Well-Known Member
jijiandfarmgang said:
Don't go on a wild goose chase, chasing what someone says is the latest and greatest growing secret.

Forget the UVB, CO2, new generation LED lighting, magic sauce supplements or any other snake oil out there. Stick to a basic growing method.

If you want to use HEPA for intake filter, go ahead, but you really need to upsize your intake fan as they are a restriction.

Like you said mold is everywhere, forget about the HEPA fixing that, you need to keep your humidity in check.

- Jiji
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None of those are really new.

LED is just more efficient, not going to give you any more/better compared to any similar size and spectrum system.

CO2 is proven, but one hella bitch to bother with.

UVB is pretty solidly supported, but the claims are yet to be lab tested. A couple of us are talking about getting that done soon. It's been around and used by a number of top growers for over 20 years. You can find the side by side bud pics and see the difference. There is one I saw where one side of a cola was exposed, so you could actually see on the same bud what it looked like with and without UVB, dramatic difference.
 
WeekendSupervisor

WeekendSupervisor

Well-Known Member
Ed Rosenthal speaks on UV-B light in a way that made me think it's science. We are trying to emulate the sun's radiation in our little rooms inside. He and others quote a particular thesis by John Lydon.
Effects of UVB radiation on THC and Trichrome Production (LINK)

I'm not using UV-B yet, but I'm new and I'm not discounting using UV-B in the future. I know a lot of people are just trying to sell you crap, I don't think this is one of those cases. My $0.02USD
 
WeekendSupervisor

WeekendSupervisor

Well-Known Member
That being said, jijiandfarmgang has experience, and when she says you should master basic grow first, that is probably sound advice.:bigjoint:
 
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f0nzy

New Member
OK so maybe I'm asking the wrong questions. I'm going to save my next question for a new thread. Maybe I can do this the proven/traditional way, in a much more cost effective fashion. Thanks for the ideas, I'm going to consider them all (jiji's too).
 
sold777

sold777

Well-Known Member
Yet agin another interesting thread, so I just pop out and got jungle dawn led UVB so lest see.
Regards
 
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