Exhaust for 4x8 tent
- Thread starter Jcann
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JoeBlow5823
Well-Known Member
Yeah that should probably get the job done. I would go with at least 400cfm fan though especially if u r using a carbon filter. You will want one with a speed controller.
For sure. I know I’ll be going with the AC Infinity, just trying to make sure I get the right one
JoeBlow5823
Well-Known Member
The 6 inch moves quite a bit of air. I never turn the 6 in my 5x5 above 75% and i run a 1000w double end HPS. I do have my 6'' fan connected to a 8'' filter though.... The bigger the filter the less restriction and more smell it can absorb. The shitty old fan in the pic is now an ac infinity but u get the idea. I also have like 15 foot of ducting and a bunch of weird twists and the air has to go through that hood so lots of restriction. And i run my light at 1100w. So I do not see u having issues with 800w
I’m going to have 2 800W lights in there. Still think that’s enough?
JoeBlow5823
Well-Known Member
Thats a lot of light. I guess i might go with the 8'' just to really move some fucking air to give them every chance of handling all that light. You can always run a fan at a lower speed but once you get to 100% you cant turn it up any higher. Those fuckers put out as much light as my double ended 1000w. Im not saying i know for a fact its to much light, but im kind of thinking it is.
Too much light? How is that possible? Lol. More light = bigger buds /s
The light is rated for a 4x4 footprint in flower. So, it will take 2 lights to cover a 4x8 canopy. I run 1 currently in my 4x5 and had no problems even with the light as close as 6” from the canopy.
coreywebster
Well-Known Member
Its going to depend on the ambient air temp
If you live in 24 degrees and want to be at 28 degrees it takes a lot more air exchange to maintain than it would if you lived in 20 degrees and wanted to be at 28 degrees.
It boils down to CFM = 3.16 x Watts / DT(°F)
Watts is the lighting power (and any other 'hot' things in the grow space) in Watts.
DT is the allowable temperature rise within the enclosure (i.e. desired temperature minus ambient temperature) in °F.
Easier to deal with Fahrenheit
74f to 82f is a dt of 6f
cfm = 3.16 x watts / 6 (dt)
3.16 x 1600 divided by 6 = 843cfm
If your at 20c or 68f then the dt is 14f (assuming you want to be at 82f)
So 3.16 x 1600 divided by 14 = 362cfm
This doesn't include filter and duct losses.
Always work to worst case , been summer temps.
If you live in 24 degrees and want to be at 28 degrees it takes a lot more air exchange to maintain than it would if you lived in 20 degrees and wanted to be at 28 degrees.
It boils down to CFM = 3.16 x Watts / DT(°F)
Watts is the lighting power (and any other 'hot' things in the grow space) in Watts.
DT is the allowable temperature rise within the enclosure (i.e. desired temperature minus ambient temperature) in °F.
Easier to deal with Fahrenheit
74f to 82f is a dt of 6f
cfm = 3.16 x watts / 6 (dt)
3.16 x 1600 divided by 6 = 843cfm
If your at 20c or 68f then the dt is 14f (assuming you want to be at 82f)
So 3.16 x 1600 divided by 14 = 362cfm
This doesn't include filter and duct losses.
Always work to worst case , been summer temps.
Last edited:
JoeBlow5823
Well-Known Member
If that is your experience with that light you should be fine, I have no experience with it. Go with an 8'' just to be safe, they dont cost that much more.
KingQuazy
Well-Known Member
Personally, I'd just buy an identical fan. You're doubling the tent, you're doubling the light.. it makes sense to me. This way, you can force one in and keep one running out. Due to one being up high and the other being down lower, it should in theory give you a much better air pattern as well.
Edit: As said above, I would def look into upsizing the filter too. I really like that idea.
Edit: As said above, I would def look into upsizing the filter too. I really like that idea.
Barristan Whitebeard
Well-Known Member
Which inline fan did you buy, the 8" Terrabloom EC fan?
Yep, exactly. I was going to go with the ac infinity but they were out of stock and I don’t have time to wait. I’m a little nervous cause I don’t know anyone with first hand experience with the terrabloom. However, I like that I can dial it all the way down based on need and I have an ink order controller I can hook it to.
pulpoinspace
Well-Known Member
800w is too much for a 4x4 imo i think those 10 bar lights are designed for a 5x5
tbh i would probably even dim the 640w 8 bar model in a 4x4. i run a 6" inline fan and keep it controlled to about 40-50% and dont have problems with temps but i only run about 560 total watts in my 4x4. 480w of qbs and 80w of UVB flouros.
50w/sqft of high efficiency LED is a lot i hope your environment and nutrients are dialed in cause those plants are gonna be under some pressure. if you do a grow journal with those lights please link it i'd be interested in following along. those lights look super nice!
good luck to ya.
tbh i would probably even dim the 640w 8 bar model in a 4x4. i run a 6" inline fan and keep it controlled to about 40-50% and dont have problems with temps but i only run about 560 total watts in my 4x4. 480w of qbs and 80w of UVB flouros.
50w/sqft of high efficiency LED is a lot i hope your environment and nutrients are dialed in cause those plants are gonna be under some pressure. if you do a grow journal with those lights please link it i'd be interested in following along. those lights look super nice!
good luck to ya.
the mammoth 10 bar covers a 5x5 canopy in veg and a 4x4 canopy in flower.
Take a look at my Grow journal. I lost one of 6 while trying to get my drip timers and another hermed late flower but otherwise, I’ve got 4 very dense plants drying as we speak.
I only use the mammoth for flower and when I went to flower I gradually increased the light to 100% over the course of the first 10 days.