400 or 600 in my new tent

[moonboots]

Hi Guys here is my 1st post ever!!! popping my cherry so to speak.

I have a 2x4x7 tent currently running a 400w HPS w/built in ballast lamp and a dayton 265 cfm fan . Total of 8 plants (4 ed rosenthals & 4 GDP) in soil.

I am thinking about switching to a 600w HPS cooltube w/digi ballast, but I am not sure if the extra wattage would be a waste in such a small space. I do have a 442 vortex fan I could use for additional cooling. Let me know what you think.

Thanks,

Moonboots

[Mist]

With 8 plants in that area you would probably benefit from stepping up to the 600. It will give you more lumens, a larger footprint for better coverage and better light penetration in what will probably be a thick canopy in that small of an area. I have 2 600's for a 4X5 area and it really makes a difference.

Go big or go home, LOL!

[2fast4u2]

uh,,,,,......... for a 2x4 i would ONLY go with 2x 250w. air cooled

If you know anything about lighting, then you would also know that for a tent of that design would require more than one light to have an effective footprint.

400w is just wrong, and a 600w is gonna create too much heat i fear, and a 600w'rs usable footprint is 3', that leaves one foot with out the possibility of a 5000 lumen saturation,

what do i know.


good luck

2fast

[darookie2000]

uh for a 2x4 i would ONLY go with 2x 250w. air cooled

If you know anything about lighting, then you would also know that for a tent of that design would require more than one light to have an effective footprint.

400w is just wrong, and six hundred watt is gonna create too much heat i fear, and a 600w usable footprint is 3', that leaves one foot with out the possibility of a 5000 lumen saturation,

what do i know.


good luck

2fast
I have a 600W in a tent that's about 3x5 and it works well. An air cooled hood takes all the heat out. The footprint is a bit bigger than 3' - maybe a little bit more narrow than I need, more like 4x4, but it works fine, I just need more space at this point (and of course more light). It can work, but if I was going to recommend 2 lights I'd go with 2 400s.

[2fast4u2]

Click HERE (http://www.icmag.com/ic/album.php?albumid=8734) for pics of my setup.

[2fast4u2]

I have a 600W in a tent that's about 3x5 and it works well. An air cooled hood takes all the heat out. The footprint is a bit bigger than 3' - maybe a little bit more narrow than I need, more like 4x4, but it works fine, I just need more space at this point (and of course more light). It can work, but if I was going to recommend 2 lights I'd go with 2 400s.

2 400w???? Ok, now i can pull that off in that space, but I also overkill any ventilation setup i run, most do not.

2 400w'ers and hes gonna have heat issues.

maybe not, and if he can pull it off, then of course DO IT! lol, lumens = fat sloppy buds.

ps, i run a 1000w and its "usable" footprint at best is 4', not sure where you believe a 600w has a 4' footprint. Simply not the case.

My buddy runs 1 600w in a tent as big as mine, but his yields suck compared to my tent.

lumens are lumens.

[2fast4u2]

8 sq ft x 50w per sq ft =400w

5000 lumens per sq ft =40,000 lumens needed.
well, two 250w'ers would exceed that by 20,000 lumens

he really only needs 400w of lighting, but it would have to be distributed better. (more bulbs, less wattage per)


math doesnt lie.

[moonboots]

Thanks for the input guys, funny enough I was able to run the same 400 in a homebox S which was 2x2x4 and actually got a few good grows out of it.

I am running the 400 right now, aircooled with no temp issues. I am just wondering if bumping to a 600 will make that much of a yield difference since a 400 is the only light I have ever used. Heat was a pain the butt to control in that small of a space but the grow came out pretty well.

[darookie2000]

2 400w???? Ok, now i can pull that off in that space, but I also overkill any ventilation setup i run, most do not.

2 400w'ers and hes gonna have heat issues.

maybe not, and if he can pull it off, then of course DO IT! lol, lumens = fat sloppy buds.

ps, i run a 1000w and its "usable" footprint at best is 4', not sure where you believe a 600w has a 4' footprint. Simply not the case.

My buddy runs 1 600w in a tent as big as mine, but his yields suck compared to my tent.

lumens are lumens.

Depends on the reflector partly, I got a much bigger footprint by changing to a magnum from a cooltube.

[2fast4u2]

Depends on the reflector partly, I got a much bigger footprint by changing to a magnum from a cooltube.

?????

What does the reflector have to do with the inverse square law?

sorry friend, not sure what you are talking about, lol.

Increasing the available projection doesnt apply to this convo, outside of three feet the light is diminished, even if the bulb had no reflector, it would be 360 degrees of weaker light, get it? the fact that you are dispersing your light over greater area proves that.

good luck

2fast

[2fast4u2]

Thanks for the input guys, funny enough I was able to run the same 400 in a homebox S which was 2x2x4 and actually got a few good grows out of it.

I am running the 400 right now, aircooled with no temp issues. I am just wondering if bumping to a 600 will make that much of a yield difference since a 400 is the only light I have ever used. Heat was a pain the butt to control in that small of a space but the grow came out pretty well.

funny, thats what i veg with, lol. my smaller tent if you will.

400w
homebox s
330 cfm fan/ carbon filter
http://www.icmag.com/ic/picture.php?albumid=8734&pictureid=158493

[darookie2000]

?????

What does the reflector have to do with the inverse square law?

sorry friend, not sure what you are talking about, lol.

Increasing the available projection doesnt apply to this convo, outside of three feet the light is diminished, even if the bulb had no reflector, it would be 360 degrees of weaker light, get it? the fact that you are dispersing your light over greater area proves that.

good luck

2fast
If the light is condensed on one hotspot it can't be elsewhere. I don't want to get into an argument about it, if I'm wrong I'm wrong. I'm not even sure we're talking about the same thing. If you mean 3' as in the height from canopy, we're not. That's how the inverse square law would usually be applied as far as I can tell. Maybe diagonal distance from the source, but I haven't really measured that.

Here are a couple of separate lighting guides from vendors.

http://www.futuregarden.com/knowledge_tree/about_hydroponics_hydroponic_l ighting.html
http://www.futuregarden.com/lighting/lighting_hidcov_chart.gif

http://www.who-sells-it.com/cy/worm-s-way-inc-1904/hid-systems-7825/page-1.html

http://www.who-sells-it.com/images/catalogs/1904/7825/ct/normal_hid-systems-000001.jpg

If you check out pico's thread, you will see that he tested a bunch of different reflectors by measuring the light intensity at a number of different areas under the reflector.

[2fast4u2]

Seedbanks also say strains flower in 45-50 days. sure some do, but again, yeah.

funny, ive never seen a 1000w grow over a 6'x6' flood table.

I guess we will have to agree to disagree, reflectors can balance a footprint, but CANNOT increase lumen output.

According to these claims, i should have a 600w in my tent??? yeah if i want paltry yields, lol.

The sun is 10000 lumens, im not far off. With the six hundred i would be at the bottom requirement of 5000 lumens.

Gram a watt much?

Subpar lighting is not my dept.

[darookie2000]

Seedbanks also say strains flower in 45-50 days. sure some do, but again, yeah.

funny, ive never seen a 1000w grow over a 6'x6' flood table.

I guess we will have to agree to disagree, reflectors can balance a footprint, but CANNOT increase lumen output.

According to these claims, i should have a 600w in my tent??? yeah if i want paltry yields, lol.

The sun is 10000 lumens, im not far off. With the six hundred i would be at the bottom requirement of 5000 lumens.

Gram a watt much?

Subpar lighting is not my dept.

I'm not saying a 600 should be used in place of a 1000, more light is obviously better if heat is not an issue. I'm also not saying that I would use a 1000 over a 6x6 space. If I was growing in a 6x6 space, I'd probably have 3 or 4 600s covering. I'm not sure I get why you're saying that because you'd get less with less light that makes a 600 unusable. His question was if a 600W light would work over a 2x4 space, my assertion is that it can.

You said that you need 5000 lumens per square foot. That makes sense, a 600W light is 90,000 lumens, 2x4 is 8 square feet. 90,000/8 = 11250 lumens/sq ft, and that's not enough? Maybe I'm a confused stoner, but comparing the output of a 600 and a 1000 in the same size tent doesn't make any sense... I never said you'd get worse output from a 1000W light than a 600 (unless you have to get it so far from the tops that you get more light intensity from the 600). I have a reflector that dissipates heat so well that my tops are 2 inches from the glass. Wouldn't that give me more lumens than a bulb that had to be 2 feet higher even if it was a 1000? I haven't done the math, but my suspicion is that the inverse square law would make a difference.

Lol, okay, I'm done hijacking.

Yes, a 600 will be fine in that space. Just make sure you keep it cool. If you would rather have two lights, I wouldn't waste my money on bulbs smaller than 400W, personally, it just doesn't seem worth it. 250s have like an 18 inch square usable space, which probably won't get you all the way to the corners. If you are going to use bulbs that small, I suspect T5s might be a better use of the money. I personally have hardly ever calculated lumens per square foot prior to this discussion, because, quite honestly, lumens are not even that useful of a measurement for plant lights. Lumens measure human perception, so while they are good for comparison purposes, they aren't particularly useful for hard and fast calculation. There are many different ways to light a space, and there is no right answer. Generally speaking, more light is better and two bulbs of a size smaller are better than one bulb of the next size. In other words, two 400s would be better than a 600. Two 600s would be better than a 1000 (counting straight lumens, 3 600s are actually better than 2 1000s in most cases because of the canopy distance). I don't think I'd say that 2 250s (two sets of ballasts and hoods, and bulbs to replace don't sound too appetizing to me) would be better than a 600, personally, but that's just my opinion for my growing space. I could be wrong, but that's okay, it still works for me.

[habeeb]

cool tubes suck

whats the heat? get it if you can deal with the heat, I would say temps are just as important as light

[2fast4u2]

I'm not saying a 600 should be used in place of a 1000, more light is obviously better if heat is not an issue. I'm also not saying that I would use a 1000 over a 6x6 space. If I was growing in a 6x6 space, I'd probably have 3 or 4 600s covering. I'm not sure I get why you're saying that because you'd get less with less light that makes a 600 unusable. His question was if a 600W light would work over a 2x4 space, my assertion is that it can.

You said that you need 5000 lumens per square foot. That makes sense, a 600W light is 90,000 lumens, 2x4 is 8 square feet. 90,000/8 = 11250 lumens/sq ft, and that's not enough? Maybe I'm a confused stoner, but comparing the output of a 600 and a 1000 in the same size tent doesn't make any sense... I never said you'd get worse output from a 1000W light than a 600 (unless you have to get it so far from the tops that you get more light intensity from the 600). I have a reflector that dissipates heat so well that my tops are 2 inches from the glass. Wouldn't that give me more lumens than a bulb that had to be 2 feet higher even if it was a 1000? I haven't done the math, but my suspicion is that the inverse square law would make a difference.

Lol, okay, I'm done hijacking.

Yes, a 600 will be fine in that space. Just make sure you keep it cool. If you would rather have two lights, I wouldn't waste my money on bulbs smaller than 400W, personally, it just doesn't seem worth it. 250s have like an 18 inch square usable space, which probably won't get you all the way to the corners. If you are going to use bulbs that small, I suspect T5s might be a better use of the money. I personally have hardly ever calculated lumens per square foot prior to this discussion, because, quite honestly, lumens are not even that useful of a measurement for plant lights. Lumens measure human perception, so while they are good for comparison purposes, they aren't particularly useful for hard and fast calculation. There are many different ways to light a space, and there is no right answer. Generally speaking, more light is better and two bulbs of a size smaller are better than one bulb of the next size. In other words, two 400s would be better than a 600. Two 600s would be better than a 1000 (counting straight lumens, 3 600s are actually better than 2 1000s in most cases because of the canopy distance). I don't think I'd say that 2 250s (two sets of ballasts and hoods, and bulbs to replace don't sound too appetizing to me) would be better than a 600, personally, but that's just my opinion for my growing space. I could be wrong, but that's okay, it still works for me.

okay, we are def saying similar things but not on the same page.

i would absolutely run 4 250's over my 1k!

Should i have mentioned im a sog guy??? would that make more sense as far as my views on light distribution and intensity??? my canopy in hydro is pretty flat and even (for the most part)

[Mist]

Hmmm, I just finished a grow in a 4X5 area with 7 plants and this is what I got out of it>



http://www.icmag.com/ic/picture.php?albumid=5755&pictureid=142736&thumb=1 (http://www.icmag.com/ic/picture.php?albumid=5755&pictureid=142736)

So obviously a 600 would work in a 2X4 area just fine. I have 12 plants going in there now and added another 600 for better coverage.

[2fast4u2]

Hmmm, I just finished a grow in a 4X5 area with 7 plants and this is what I got out of it>



http://www.icmag.com/ic/picture.php?albumid=5755&pictureid=142736&thumb=1 (http://www.icmag.com/ic/picture.php?albumid=5755&pictureid=142736)

So obviously a 600 would work in a 2X4 area just fine. I have 12 plants going in there now and added another 600 for better coverage.

not saying it wouldnt work, just that he could trump that yield with 2 250's.

closer to the plants and better distribution, even with less wattage:joint:
light intensity, kind of theory when growing, but its true. So many other factors tho.

[darookie2000]

okay, we are def saying similar things but not on the same page.

i would absolutely run 4 250's over my 1k!

Should i have mentioned im a sog guy??? would that make more sense as far as my views on light distribution and intensity??? my canopy in hydro is pretty flat and even (for the most part)
Huge difference, lol, my plants are 5 feet tall and 250s would kill my yield. It wouldn't be worth it for me to buy less than 400s, the canopy penetration is just not enough. The canopy depth on a 250 is like 18 inches which is way too short for me.

[Mist]

Well the issue here is that 2fast4u2 us doing a sea of green where he needs no light penetration. All he is trying to do is hit the tops with some light. For us full size plant growers his suggested light setup is way too weak. So all this argueing is getting us nowhere.

[darookie2000]

Well the issue here is that 2fast4u2 us doing a sea of green where he needs no light penetration. All he is trying to do is hit the tops with some light. For us full size plant growers his suggested light setup is way too weak. So all this argueing is getting us nowhere.
Yep :) we know that now

[moonboots]

Last time I did a 4 plant Scrog in my small tent and yielded a little over a qp. I was hoping to get close to a P this time as I have doubled the amount of plants with a greater height capacity. Is that a realistic goal?

I was thinking about getting the 600 for better penetration, so I can grow them to about 3-5 feet tall.

Or do you guys think yield would be higher just using the 400 or 600 in a scrog setup again?

BTW my current temps ate running from 76-82, unfortunately I am recirculating the air back into the same room which is about 15x15, and airing out at night (window fan). The room is also AC'D.

Thanks again for the input.

MB

[moonboots]

http://icmag.com/ic/picture.php?albumid=9539&pictureid=178280http://icmag.com/ic/picture.php?albumid=9539&pictureid=178279http://icmag.com/ic/picture.php?albumid=9539&pictureid=178278 (http://icmag.com/ic/album.php?albumihttp://icmag.com/ic/album.php?albumid=9539&pictureid=178280d=9539&pictureid=178278http://icmag.com/ic/album.php?albumid=9539&pictureid=178279)

[californiajoe]

interesting info.

[2fast4u2]

just beautiful, nice job!

just goes to show that a homebox s can pump out weight, all in how you grow and manage your available lighting.

thanks for posting that pic, goes to show.

[2fast4u2]

Well the issue here is that 2fast4u2 us doing a sea of green where he needs no light penetration. All he is trying to do is hit the tops with some light. For us full size plant growers his suggested light setup is way too weak. So all this argueing is getting us nowhere.


not quite,

a 250 will have the same penetration as a 1000w.

1000w'ers typically are hung at least a few feet above the canopy.

A 250 can sit on the plants making use of all the light, the available canopy real estate on a 5 foot plant only goes down from the top to about 2 feet, after that without lollipopping you are talking straight airy buds.

Im really trying to help the op, ive had several debates over lighting theory and am pretty much saying what i learned from people in the know, and what i felt was common knowledge.

Im new to this particular site, so the "climate" regarding lighting could be very different here.



2fast

[californiajoe]

fwiw, op, i have a growlab 3'11x3'11x6'7'' or something like that with a 400w hps on 6 bubba kushes in an ebb and grow and i am really wishing already that i would have gotten set up with a 600w.