Cool tubes or nah?

HydroUK

HydroUK

Member
I've been recommended to use cool tubes by a fair few people now, however I've also seen people say they have terrible/uneven light coverage due to the small reflector.

According to a few posts I've seen, the lower temperatures produced by the tubes stimulate denser bud growth and therefore make up for the lost reflected light. Is this true?

Finally, can anyone recommend some 600w cool tubes with a bigger reflective hood/attachment?

Thanks in advance
 
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Dr. Who

Dr. Who

Well-Known Member
Hmmm.....
How big is the growing area?

Both would work,,,,,here in the "colonies", 5 inch ducting is kinda hard to find......6 is the "normal" and 8 is always available too.
For you, 8 is big time overkill.....

Doc
 
hotrodharley

hotrodharley

Well-Known Member
Go with the smallest tubing and fastest fan you can find. The smaller lumen increases the velocity (speed its up) and the efficiency in moving air. This goes in carburetor venturis on hot rods or anything else. If you go 6" you best buy the heaviest duty fan you can find to make use of all the space. Go small at first for small grows.
 
HydroUK

HydroUK

Member
Dr. Who said:
Hmmm.....
How big is the growing area?

Both would work,,,,,here in the "colonies", 5 inch ducting is kinda hard to find......6 is the "normal" and 8 is always available too.
For you, 8 is big time overkill.....

Doc
Click to expand...
Most likely 5 x 6 x 6 but I have an 8 x 8 ft area to work with, should I need extra space.

I'll have 3 x 600w lights, I'm wondering if these will cool it down too much in the winter (UK), especially taking into account that the place I'm doing it in has 1 inch walls.

If it isn't and I end up using them I have 3 more questions:
1) Should I have an extractor fan pulling heat away or a fan pushing cold air onto the bulbs? I've heard pushing is the way to go.
2) Should I use the 'T' aka parallel setup to stop the last light from being too hot or does this not matter? I'm pretty maxed out budget wise and could really do without buying all the extras for the second image. Should I just use a 5" in series or is parallel a necessity?
3) I'm presuming I need 3 fans for this to work? 1 Intake, 1 extractor & one cool tube intake fan, is this correct?

Really appreciate you guys taking the time to answer these.
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HydroUK

HydroUK

Member
hotrodharley said:
Go with the smallest tubing and fastest fan you can find. The smaller lumen increases the velocity (speed its up) and the efficiency in moving air. This goes in carburetor venturis on hot rods or anything else. If you go 6" you best buy the heaviest duty fan you can find to make use of all the space. Go small at first for small grows.
Click to expand...
Perfect thank you man! You give some of the best answers I've seen on the forum.

What do you think about having 3 x 600s in series? Will the 3rd one be dramatically hotter even if I use a pretty heavy duty fan? So I've decided on 5" due to your advice, how powerful are we talking fan wise & is there a way to buy a totally overkill fan and divide the cool air between the lamps & the actual grow room? I could really do without spending the extra $60-100 on another fan.

Thanks again.
 
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hotrodharley

hotrodharley

Well-Known Member
If you know someone halfway skilled at sheetmetal work you can have them build a reducer. Buy an 8" fan and neck the outlet with a reducer to 5". That alone will speed up the air going into the outlet. Or add a 5" fan between the units to again speed up the air that is quickly slowing. 3 in a series is going to be hot but the 8" fan should cool it okay or adding a 5" between the 2nd and 3rd lights should help greatly. Building supplies might have reducers already available as it is common to reduce the pipe sizes as the run goes on.
 
Dr. Who

Dr. Who

Well-Known Member
HydroUK said:
Most likely 5 x 6 x 6 but I have an 8 x 8 ft area to work with, should I need extra space.

I'll have 3 x 600w lights, I'm wondering if these will cool it down too much in the winter (UK), especially taking into account that the place I'm doing it in has 1 inch walls.

If it isn't and I end up using them I have 3 more questions:
1) Should I have an extractor fan pulling heat away or a fan pushing cold air onto the bulbs? I've heard pushing is the way to go.
2) Should I use the 'T' aka parallel setup to stop the last light from being too hot or does this not matter? I'm pretty maxed out budget wise and could really do without buying all the extras for the second image. Should I just use a 5" in series or is parallel a necessity?
3) I'm presuming I need 3 fans for this to work? 1 Intake, 1 extractor & one cool tube intake fan, is this correct?

Really appreciate you guys taking the time to answer these.
View attachment 3492909
View attachment 3492895
Click to expand...
2 will be all the lights you need for that area (5x6x6) for now.. If you go 8x8x6 - you'll need 4 ,, 1 per 4x4.
Go with the 6"

1: PULLING!!!!
2: NO any time you add a turn or a "T", you reduce the effective cfm - "T"s are worse.
3: 2 only! One for light cooling......One for at the vent out - in effect, your pulling air in and forcing it out. The shorter/straighter the line out, the better. mount the fan to a metal vent out at the wall it's self = best. Filter the air intake as best you can (not a charcoal scent filter). A filter to keep out mold spores and bugs.

Doc
 
hotrodharley

hotrodharley

Well-Known Member
A T slows air faster than an ugly woman's face can wilt a hard Johnson. So does making the exhaust larger in any way. 3 lights in a row are a furnace sothe good doctor is right. Limit it to two. Heat is one of your biggest enemies always.
 
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