Ok that’s good to know too.
I actually meant a metal clamp like one of these:
I’ll add a duct tape seal on top of this from now on to make sure it’s really airtight.
I’ll add a duct tape seal on top of this from now on to make sure it’s really airtight.
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Haha.
I’ve read that it’s better and more effective to pull the air through the carbon filter by attaching it pre-exhaust fan, rather than pushing the air through the filter. It was years ago, but I think I remember that setting it up that way also increases the life span of the filter. That’s how I’ve always done it, anyway.
I hang the carbon filter in the back of the tent and attach it to the exhaust fan with just a little bit of ducting it, like six inches or so. I’ve never attached the filter directly to the fan before, although I think I’ve seen some people do that. Also, I use bungee cords to hang the filter, makes it easier to get it down when I need to put the the carbon filter’s pre-filter in the wash after every grow.
I dunno what kind of tent you use, but remember that hangin the filter is gonna add more weight.
I think hanging it is “better,” too, just because putting it on the floor of the tent means there’s that much less room for more plants haha. I’d also imagine that having any plants near a filter on the floor of the tent would mean that the plants closest to it it would get pulled towards the filter/fan.
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I wouldn’t use duct tape; those things (I can never remember what they’re called, either haha; “duct fasteners,” maybe? Haha!) work fine, just make sure you tighten them really well. If you use duct tape, every time you need to deal with the carbon filter, you’re gonna have to peel it off and shit.
Also, I forgot to really address this:
That’s awesome! Haha.
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Thanks minitiger this is all gold. I started off as an outdoor grower, so I never really had an education in grow room setup. When I started growing indoor I just made it up as I went along and did whatever was most simple.
Ok I think that makes sense to me, you put the inline after the fiter to use its power on the point of highest resistance. at least that’s how it makes sense in my head.
I bet I can still use a hepa filter as a dust catcher in front of the carbon filter to keep it from getting clogged up with pollen and other particulates.
Yeah these are fairly old, hopefully they are still sturdy enough for this. I’ll keep weight and balance in mind.
Yeah that would give me room for an extra pot in each tent, that’s an appealing prospect.
I’d also imagine that having any plants near a filter on the floor of the tent would mean that the plants closest to it it would get pulled towards the filter/fan.
I’ve used a hepa filter to keep anything from getting sucked into the inline, but the plants closest to it definitely dry out a little faster than the rest of the tent. so that change might make watering a little easier if I didn’t have that litle microclimate in the tent next to the fan.
I think the only thing that I’d be losing with this setup is the natural convection air movement that I get from having the intake at the top of the tent and the exhaust at the bottom. that really gets the air circulating. Maybe I’ll try moving my intakes to the lower vent ports.
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Yeah it’s hard not to take these complaints about the smell as a compliment hahaha
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Well, simple’s always best, but I know what you mean. I get frustrated really easily, no patience at all, so I’m lucky my girl was there to offer easy solutions. Who knows how I would have set my shit up otherwise… ? Haha. I mean, bungee cords? Why did she even have a bunch of bungee cords? I have no idea, never asked haha.
Sure, if you want. That just sounds like extra work to me, but if you wanna keep the carbon filter outside of the tent and post-outtake fan, then, yeah, I’d definitely put something in front of the outtake fan.
What I remember reading, now that I’m thinking about it, is that your fan has to “work harder” if it’s set up like that, decreasing the life span of both the fan and the filter and also not being as effective in dealing with smells. Having never done it any other way, I can’t attest to whether or not that’s actually true. I’m still on the same outtake fan I’ve been using for the last eight years, so maybe there’s something to that.
Oh, that’s how you have it set up? I didn’t realize that. I have it the opposite, with my passive intake on the bottom and the outtake on the top. I use one of those Dust Shroom things on the intake, outside of the tent, at the bottom in the front of the tent and the outtake at the back, pulling the cooler air from the floor and kind of “across” all of the plants.
If I lived in the PNW, though, I’d probably have it set up like you do, with the dryer, hotter air getting pulled from the top and down towards the bottom of the plants. Probably helps with humidity issues and lower temps, too. Shit… Maybe scratch everything I just said haha!
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In the past this hasn’t been a problem, I use LEC light emitting ceramic and fluorescent which doesn’t generate much heat. I have circulating fans to keep air moving in the room, and a portable window ac unit running in the room is enough to keep it cool in summer. In the winter the lights and the house furnace keep it warm enough.
So I never had to pull heat away from hot hps bulbs, or run cool tubes for lights or anything.
But I think I’m going to make some major changes to the setup now.
I’m going to take down the AC unit for the winter and run all the tent exhausts directly out the window, using a window card like the one for the portable ac. I think that change plus the carbon filter for the flower tent will take care of my indoor smell problems.
any smell outdoors should be manageable and dissipate quickly.
I’m definitely going to run it with the carbon filter in front of the inline, and hang it all from the tent frame. The added floor space alone makes it worthwhile, but hopefully it will also run a little quieter and be more efficient with the carbon filter.
I can probably keep the convection going by just running a vent tube down from the filter into the lower corner of the tent where I used to have the inline set up. That way I can hang it but still pull the air out from the same spot in the tent. shouldn’t increase resistance by much either.
I use the hepa filter material the same way you use that mushroom filter. I actually bought something like that one time, but weirdly it came soaked in rosemary oil so I returned it.
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Yeah, that’ll totally work (unless those plants are just TOO DANK haha). That’s actually how I vent all year ‘round, right out the window. I didn’t realize you were just venting the air from the tent and back into the room. I do that with the veg tent; the little Apache I have in there generates zero heat. I actually wish it would get at least slightly warm, gets too cold in the veg tent most of the time.
I think that was one of the things the bungee cords were helpful with, too, along with not attaching the filter directly to the fan, was that it cut down on, like, making the whole tent frame kind of vibrate. If you’re living in an apartment especially, I’d imagine that that shit’ll move from floor to floor and piss off your upstairs or downstairs neighbors. Or both haha.
Why not just run the venting ducting straight from the filter to the fan to the outside of the tent at the top? And run the ducting out of the top “exhaust hole” or whatever they’re called? The more twists and turns there are, the less effective it’ll be, although those fans are powerful as shit, so it probably wouldn’t matter.
Hahaha… I know, they do come soaked in all kinds of essential oils. Whenever I buy a new one, I have to put Saran Wrap underneath it so the floor doesn’t get oil all over it. And a stand to rest it on so that it doesn’t dangle from the tent, it’s a whole thing…
I may have to look into these hepa filters haha…
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that’s what I’ll be doing.
If it turns out I really need the top to bottom convection because of humidity and moisture issues, all I would need to keep the airflow pattern the same would be a short length of tubing on the inlet side of the carbon filter. so the equipment at the top of the tent can suck air from the same area at the bottom corner of the tent and keep my top to bottom convection going.
if I get any moisture buildup or dewdrops on the leaves that’s how I’ll solve it.
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Ahh, I would have called those hose clamps haha.
So the filter and fan at the top of the tent with the exhaust going out the hole in the side of the tent, then out a window will work, but the air in the room the tent is in will then need to be replaced as it is blown out the window. I mean passively replaced by the way, not that you would then need another fan or something. Might not matter for you depending on climate, but worth considering. For instance, if I had a 6” fan ducted out the window in the winter, my house would be freezing, because all the air getting pushed outside would be getting replenished by cold air coming in any leaky doors or windows.
I don’t know what you mean by a piece of duct on the inlet side of the filter. All the filters I have ever used only have one duct opening, and the air is blown or sucked through the hundreds of small holes that are in the outside wall of the filter. Unless you found an inline carbon filter, which might exist, despite my not knowing about them. If you wanted to circulate the air top to bottom in the tent you could use a small fan on the floor or ceiling of the tent pointed up, or down depending.
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Also, way late on this, but if you do not need it to be 100% smell free, you can just take a fan with a carbon filter attached to it, and place it in the same room as the tent. Won’t be perfect, but it does help some, and it is an instant “solution”, assuming you have a spare fan or can get ahold of another. It also means you wouldn’t have to change the ventilation in the tent all at once, that’s always a bigger job than it seems like it is going to be.
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thanks for all the input @potpotpot and @minitiger.
the vents are all set up now. I think hanging the fans was an improvement for noise and vibrations, and I’m not smelling the plants when I get up in the morning and walk past the grow room. I didn’t even smell it when the lights shut off in the flower tent a few minutes ago.
Hopefully that takes care of it. When I chop this next batch of flowering plants, I’m going to hang my drying rack in the tent so I won’t have to worry about any smell from the freshly harvested bud as it dries. That will set back my schedule, but I think it will be worth it.
You were right about that for sure haha.
Thankfully I had help from my MMJ caregivers, but it still took 3 days to get it all done.
I think some fine tuning may be needed, even with a 6" air intake on each tent and the inlines running at a lower speed than before, there is more negative pressure in the tents than with the previous setup. I like to run with negative pressure, but the tent fabric is sucked in pretty tight. May need to add a second intake to each tent to balance things out.
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Nice save! I’ve done venting all kinds of ways, but have settled on venting outside, like you’ve setup now. One benefit of venting outside is that it was way easier for me to control the humidity at lights off. You don’t dump all that humid air back into your room or tent. Also, like you were saying, the smell dissipates way faster outside and you don’t have this build up inside your space. Although, sometimes I like to bask in the stink of the plants 
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Yeah, I was like,”Awwww… Bummer…” when I read this:
Haha, but you gotta do what you gotta do. Definitely don’t wanna be pissing off the neighbors…
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I just had major setback and pest scare. My propagation tent was completely wrecked by aphids, and I lost everything in there.
It went from “everything looks good” on wednesday, to “huh these clones look a little stressed out, but I can’t find a specific problem” on thursday, to “crawling with aphids, burn it all down” today.
It had probably been brewing for a couple weeks to make a population that size, but there was no indication of a problem until the infestation was at apocalyptic levels.
a full set of unrooted clones from my usual indoor lineup was ruined, but fortunately I can go back to the mother plants for those and take new clones. So I didn’t lose anything that I selected from seed.
Unfortunately, I lost a cut that was very important to me that hadn’t been worked into the indoor lineup yet.
Everything got nuked with 90 percent alcohol. All the unrooted clones and a small plant in a fabric pot got thrown in the trash. the area got mopped with murphys oil soap, dish detergent, and thyme and lavender oil to kill any potential stragglers in the surrounding area. The tent will sit dormant over the weekend, and then it will be cleaned with bleach before striking the tent and putting it in storage for an aphid egg quarantine period.
I’m pretty sure the aphids were brought in on my outdoor harvest, which I was drying right next to the propagation tent. I never let any outdoor material come near my grow room, or tend the grow room after handling outdoor harvests or trimming. apparently that was a necessary precaution.
My outdoor harvest was definitely dirtier and more stressed out than usual this year, and I didn’t do my usual processing and trimming routine because I was only using it for seeds. I just laid it all out to dry next to the propagation tent untrimmed, and didn’t even remove fan leaves. I wouldn’t be surprised if the pests fled the drying bud to the tent. And a few times I watered the propagation tent after trimming fresh outdoor bud.
Pretty sure that’s how the pests got in. Lesson learned.
Luckily I only watered and tended to this tent after the grow room, so I hope it hasn’t spread to my grow room about 45 feet away. I will definitely be spraying everything I have in veg and hoping for the best.
I hadn’t been spraying indoors unless there is a problem, but now I will resume my maintenance and precautionary pest management spraying for all indoor veg plants.
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Late to the topic but a good brand of carbon filter a 8 inch filter fan in the tent extracted into the room your in should prevent smell exiting your apartment .
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Aphids are live births with each aphid born with 2 generations inside it. No eggs. They can fly!
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aphids are so evil. I haven’t had this happen since my first ever grow.
I brought a stunted outdoor plant indoors to flower in my seedling cabinet. actually a very similar situation to this propagation tent fiasco with aphids introduced from my outdoor harvest.
trying to decide what my next step should be. what can I spray in the grow room that won’t harm my beneficial insects? If I spray essential oils and neem, will that be safe for my spiders and beneficials as long as they are not sprayed directly?
Am I remembering correctly that ladybugs are the right beneficial predator to use on aphids specifically?
I have so many beneficials in my grow tents, I’m really hesitant to spray and disrupt this ecosystem, because it has been doing a great job protecting my plants.
I have a thriving spider population in all my grow tents which I have been working pretty hard to encourage. every time the tents get cleaned, we lovingly collect all the spiders in a plastic yogurt container and release them back into the tents afterwards. hahaha
The spiders keep the fungus gnats in check completely, and I haven’t had any other pest problems since they showed up.
I figure if I introduce a beneficial predator that specifically goes after aphids, I can manage that risk and my spiders can feast on the ladybugs afterwards.
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The portable air purifiers work great in a pinch, they cost less than a filter and fan combo but more than a DIY probably. We have them for when the wildfire smoke rolls in but the rest of the year i repurpose them. Run it in the room on blast when I sweep the floors etc. Works alright for trimming (small quantities of course).
The way things are now with clones i just think of doing a seed run with them in quarantine instead of bringing them into the flower tent. I wonder if you pick up the mt hood clone again if that would at least alleviate some anxiety and risk and provide something cool and new as well.
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Idk, ladybugs are pretty badass, have to be a decent size spider to knock that down.
I also encourage my spider IPM team, and unfortunately they seem really sensitive to any pesticide I use. Feels bad too, they almost become like free range pets haha.
My experience is that pesticides are not as targeted as they claim to be, and knockdown things way outside their labeled coverage. Sometimes they seems to do a better job at things not on the label, maybe because they are less frequently used to control them? Idk, this last bit is just conjecture and bullshit btw, if that wasn’t obvious haha
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