2x2x6 400w HPS Ventilation?

Bwpz

Well-Known Member
I am building a cabinet where I'm implementing the ScrOG method on 2 DWC buckets. Would a 400w HPS in a 2x2x6 area be overkill, or get way too hot? Would a 4.5" axial fan mounted to the mini cool tube (located here) be enough to cool it down? The axial fan it rated at 112CFM. I plan on using a 250w MH anyways since a 400w wouldn't fit in the mini cool tube.

Thanks (=
 

Bwpz

Well-Known Member
Also, does anyone know how long I should veg my clones in a ScrOG? Should I start flowering as soon as they get over the net or what?
 

psilocybindude

Well-Known Member
An axial fan is never a good idea, it is not built to push air threw a carbon filter and it is not built to suck air threw a carbon filter, it is also not built to tolerate the high temperatures that would be pumped threw an HID ventilation system, a booster fan is made for one thing, and that's boosting the air flow threw the ducting from a significantly more powerful source, your small area could be successfully vented with a 400 watt hid as long as you had a decent enough fan to exhaust the hot air.
 

Bwpz

Well-Known Member
I got 2 different answers :P

With the axial fan I don't plan on using it in conjucton with a carbon filter, just the cool tube. The 2x2x4 cabinet I have going with CFLs right now has a 50CFM axial fan cooling that whole cabinet down. I planned on using 2 112CFM fans on this new cabinet.

I didn't want to use a booster fan because that means I'd have to somehow cut a hole in the top of the new cabinet, and then I'd have to put up with the noise since it's in the room where I sleep xD
 

bazookajoe

Well-Known Member
yes the axial fan will work.. i have the same one ur talkin about coolong my 400w cooltube.. i can put my hand on the tube and keep it there for a cpl minutes, it is warm but not hot and one of my plants r less than 2 inches from the glass
 

HotShot7414

Well-Known Member
Just the right amount for 2-4 plants but 100w per sq ft is too much,75w psf is like the limit,Just keep the light 18-36" away at all times
 

Metasynth

Well-Known Member
I got 2 different answers :P

With the axial fan I don't plan on using it in conjucton with a carbon filter, just the cool tube. The 2x2x4 cabinet I have going with CFLs right now has a 50CFM axial fan cooling that whole cabinet down. I planned on using 2 112CFM fans on this new cabinet.

I didn't want to use a booster fan because that means I'd have to somehow cut a hole in the top of the new cabinet, and then I'd have to put up with the noise since it's in the room where I sleep xD

I grow in the area I sleep in AND I'm hydro...I've got 5 air pumps, 10 air stones, 2 x 16" oscillating circulation stand fans, 1 x 6" clip on circulation fan, 1 x dual 7" window fan, 1 x 6" booster fan(195cfm w.o resistance), 1 x 6" inline duct fan(450cfm), and a 5000btu AC unit. ALSO have 3 fish tanks, making an ever present gurgling.

I don't think I could sleep in a quiet room now even if I stayed up for72 hours straight...lol
 

Bwpz

Well-Known Member
I grow in the area I sleep in AND I'm hydro...I've got 5 air pumps, 10 air stones, 2 x 16" oscillating circulation stand fans, 1 x 6" clip on circulation fan, 1 x dual 7" window fan, 1 x 6" booster fan(195cfm w.o resistance), 1 x 6" inline duct fan(450cfm), and a 5000btu AC unit. ALSO have 3 fish tanks, making an ever present gurgling.

I don't think I could sleep in a quiet room now even if I stayed up for72 hours straight...lol
Both of my systems are hydro as well, and I got all that as well except that the 2 loudest things are in my closet where I can't hear them (excluding the fish tanks xD).

yes the axial fan will work.. i have the same one ur talkin about coolong my 400w cooltube.. i can put my hand on the tube and keep it there for a cpl minutes, it is warm but not hot and one of my plants r less than 2 inches from the glass
Thanks for the reassurance, I appreciate it, it'll save me a bunch of noise and $50 xD
 

Bwpz

Well-Known Member
Just the right amount for 2-4 plants but 100w per sq ft is too much,75w psf is like the limit,Just keep the light 18-36" away at all times
My closet is 2x3 and it uses a 600w MH/HPS just fine for multiple grows now, so I'm not sure how accurate those numbers are :P
 

bazookajoe

Well-Known Member
Thanks for the reassurance, I appreciate it, it'll save me a bunch of noise and $50 xD
no problem!! it works perfectly imo! i rounded off the edges so i could just fit it in the end of the tube.. well i rounded it off just not enough to get it completely inside but it still works great
ctfan.jpg
 

gorlax01

Member
You are going to want really good exhaust. I am running a 250w HPS in a 2x3.5x5ft box. My fan is 190CFM. My light is built into a custom cool tube which is then connected to a carbon filter. I also have made a booster on one end of the cool tube. My temps range anywhere from 84-88F..ambient temperature is roughly 80F-85F, sometimes cooler. I usually see a 5 degree difference from my box temps compared to the outside temps. Lights get damn hot and without the cool tube my box would be equivalent to a food warmer at KFC. Even if you have good air flow, the light is going to heat up no matter what and you can't change that. I would recommend to overshoot calculations at least if you live in the scorching desert like me!
 

huth420

Member
You are going to want really good exhaust. I am running a 250w HPS in a 2x3.5x5ft box. My fan is 190CFM. My light is built into a custom cool tube which is then connected to a carbon filter. I also have made a booster on one end of the cool tube. My temps range anywhere from 84-88F..ambient temperature is roughly 80F-85F, sometimes cooler. I usually see a 5 degree difference from my box temps compared to the outside temps. Lights get damn hot and without the cool tube my box would be equivalent to a food warmer at KFC. Even if you have good air flow, the light is going to heat up no matter what and you can't change that. I would recommend to overshoot calculations at least if you live in the scorching desert like me!
thats really high for a 250w hps
 

mr2shim

Well-Known Member
You are going to want really good exhaust. I am running a 250w HPS in a 2x3.5x5ft box. My fan is 190CFM. My light is built into a custom cool tube which is then connected to a carbon filter. I also have made a booster on one end of the cool tube. My temps range anywhere from 84-88F..ambient temperature is roughly 80F-85F, sometimes cooler. I usually see a 5 degree difference from my box temps compared to the outside temps. Lights get damn hot and without the cool tube my box would be equivalent to a food warmer at KFC. Even if you have good air flow, the light is going to heat up no matter what and you can't change that. I would recommend to overshoot calculations at least if you live in the scorching desert like me!
The room your box is in is too hot. 80-85f for a 250w? That's crazy, my tent isn't that warm and I run a 400w
 

Bwpz

Well-Known Member
With my ambient being 70-75F and having 224cfm worth of air movement I figure it should be okay :P

Does anyone know how long I should Veg my clones under the screen for in my cabinet? Just until they get over the screen or what?
 

bazookajoe

Well-Known Member
never done it but..IVE READ ull want to veg them until the majority of ur screen is filled with budsites.. leaving some holes for the branches that come up during the stretch.. HAPPY SCROGGIN:eyesmoke:
 
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