borbor
Well-Known Member
I put this up in the newbie section but I don't think I'm going to get much of a response there, I can't find a way to delete it or I'd just move it here, but here we go:
I'm currently stuffing a 3x3 tent with equipment before I get started growing. I've read a good bit about ventilation and my big question for my set up is will I want to use passive intake or get a separate intake fan? I'll probably be buying another centrifugal fan very soon no matter what, but don't know if I want to use it in this tent or just leave it until a few months down the line when I start filling up a 4x8 tent. In the 3x3 I have an lec 315 (which cannot be air cooled) and an active air 6" 400CFM cetrifugal fan. In my space, noise and smell are big issues. I'm not trying to be stealthy, it's just an agreement that I'll only be allowed to grow if the homeowner (who lives here) is convinced that my grow isn't going to bother her in the slightest. I'm working on a written proposal covering electrical costs, etc. Right now I think the obstacle between me and a green light to grow is noise. I'm thinking of putting the active air into storage til I move and getting one or two max-fans for the quiet. Not saying money is no object, just that if I have to spend an extra 500 in order to get the green light, I'll do it. Also, I haven't bought my carbon filter yet, As long as I have people here looking at my airflow set up, is a can 33 or a can 50 recommended? I got the can 33 in my cart on amazon but I'm afraid it might not be enough to scrub every inkling of smell. I really need the smell gone, I'm allowed to take dabs in the house but not smoke flower- that's how she feels about the smell.
Weighing my options with my current equipment and possibly one more duct fan-
1. I could buy one fan speed controller and turn my exhaust down a little bit to cut down on noise and still use passive intake. Only uses one fan, so it might be kind of quiet.
2. I could buy two fan speed controllers and one fan for intake, and keep them both at 50%. I've spent a lot of time building computers and my personal experience is that a fan at 100% is much much louder than when it's at 95%, and both of those are hurricanes compared to 50%. Is it the same way with duct fans?
Which of these will make less noise? which is better for my ladies? does having negative pressure in the tent make a difference?
second, I was wondering if it's a good thing to open the tent doors or windows during lights on? I know what I just said about smell, but assuming she's gone for the day or whatever. On one hand, it turns a 3x3 space effectively into whatever the size of the room you're in is, so it's probably gonna be closer to ambient temperature in there, but since the tent isn't sealed anymore, and the intake and outtake are probably in the same area, it would neutralize those, and you'd lose a reflective wall around your light. Net gain or net loss?
Third, I can remember from growing years ago that you don't want to overload circuits by plugging too much crap in to one circuit, basically if your room is one circuit and that circuit is rated for 15 amps, if the amperage of all the stuff in the room that's plugged in and on equals more than 15 amps you're gonna blow the circuit. That's my understanding. my questions, assuming I understand all of this correctly, are- what does blow the circuit mean? Just go flip the switch in the fuse box? And does it help to run extension cords all over the house so that the ballast is plugged in in the kitchen, the fans in the bathroom, etc? does it help to run cords across the room so you're using all the outlets instead of just one surge protector? At what point in size/scale/wattage should a grower even concern themselves with these things?
One more electrical question- In trying to put together a proposal to get this going, I've re-done my electrical costs sheet like four times. At this point I've already made a damn excel spreadsheet I can just type in my wattages, it spits out a cost per week in veg and a cost per week in flower. My understanding is that in my city, electricity is on a tier system so your first 500 kwh are one cost, the second 500 kwh are a higher cost, and any power used beyond that is super expensive. to make a convincing proposal, when I do the math for calculating how much my grow will cost I'm always assuming we're on that highest tier, and in excel it rounds it to 16 cents, which is fine, I'm rounding up with all the costs to make a profit for her, an offer she can't refuse.
so if during veg I use 535 watts during lights on (18 hours) and 220 watts during lights off (6 hours) at 16 cents per thousand watts an hour, (.535x1
+(.22x6)=10.95 kilowatt hours, 10.95x.16=$1.75 per 24 hours in veg?
Is that math correct?
Also, just a thought, but am I perhaps overdoing it with ventilation? I mean a 3x3x6 is really just 54 cubic feet, Do I really need over 300cfm?
Any and all answers appreciated
And if anybody expresses interest in my excel grow cost calculator I'm happy to upload that.
I'm currently stuffing a 3x3 tent with equipment before I get started growing. I've read a good bit about ventilation and my big question for my set up is will I want to use passive intake or get a separate intake fan? I'll probably be buying another centrifugal fan very soon no matter what, but don't know if I want to use it in this tent or just leave it until a few months down the line when I start filling up a 4x8 tent. In the 3x3 I have an lec 315 (which cannot be air cooled) and an active air 6" 400CFM cetrifugal fan. In my space, noise and smell are big issues. I'm not trying to be stealthy, it's just an agreement that I'll only be allowed to grow if the homeowner (who lives here) is convinced that my grow isn't going to bother her in the slightest. I'm working on a written proposal covering electrical costs, etc. Right now I think the obstacle between me and a green light to grow is noise. I'm thinking of putting the active air into storage til I move and getting one or two max-fans for the quiet. Not saying money is no object, just that if I have to spend an extra 500 in order to get the green light, I'll do it. Also, I haven't bought my carbon filter yet, As long as I have people here looking at my airflow set up, is a can 33 or a can 50 recommended? I got the can 33 in my cart on amazon but I'm afraid it might not be enough to scrub every inkling of smell. I really need the smell gone, I'm allowed to take dabs in the house but not smoke flower- that's how she feels about the smell.
Weighing my options with my current equipment and possibly one more duct fan-
1. I could buy one fan speed controller and turn my exhaust down a little bit to cut down on noise and still use passive intake. Only uses one fan, so it might be kind of quiet.
2. I could buy two fan speed controllers and one fan for intake, and keep them both at 50%. I've spent a lot of time building computers and my personal experience is that a fan at 100% is much much louder than when it's at 95%, and both of those are hurricanes compared to 50%. Is it the same way with duct fans?
Which of these will make less noise? which is better for my ladies? does having negative pressure in the tent make a difference?
second, I was wondering if it's a good thing to open the tent doors or windows during lights on? I know what I just said about smell, but assuming she's gone for the day or whatever. On one hand, it turns a 3x3 space effectively into whatever the size of the room you're in is, so it's probably gonna be closer to ambient temperature in there, but since the tent isn't sealed anymore, and the intake and outtake are probably in the same area, it would neutralize those, and you'd lose a reflective wall around your light. Net gain or net loss?
Third, I can remember from growing years ago that you don't want to overload circuits by plugging too much crap in to one circuit, basically if your room is one circuit and that circuit is rated for 15 amps, if the amperage of all the stuff in the room that's plugged in and on equals more than 15 amps you're gonna blow the circuit. That's my understanding. my questions, assuming I understand all of this correctly, are- what does blow the circuit mean? Just go flip the switch in the fuse box? And does it help to run extension cords all over the house so that the ballast is plugged in in the kitchen, the fans in the bathroom, etc? does it help to run cords across the room so you're using all the outlets instead of just one surge protector? At what point in size/scale/wattage should a grower even concern themselves with these things?
One more electrical question- In trying to put together a proposal to get this going, I've re-done my electrical costs sheet like four times. At this point I've already made a damn excel spreadsheet I can just type in my wattages, it spits out a cost per week in veg and a cost per week in flower. My understanding is that in my city, electricity is on a tier system so your first 500 kwh are one cost, the second 500 kwh are a higher cost, and any power used beyond that is super expensive. to make a convincing proposal, when I do the math for calculating how much my grow will cost I'm always assuming we're on that highest tier, and in excel it rounds it to 16 cents, which is fine, I'm rounding up with all the costs to make a profit for her, an offer she can't refuse.
so if during veg I use 535 watts during lights on (18 hours) and 220 watts during lights off (6 hours) at 16 cents per thousand watts an hour, (.535x1

Is that math correct?
Also, just a thought, but am I perhaps overdoing it with ventilation? I mean a 3x3x6 is really just 54 cubic feet, Do I really need over 300cfm?
Any and all answers appreciated
And if anybody expresses interest in my excel grow cost calculator I'm happy to upload that.