1k HPS inside 4x2 tent?

jb4TWENTY

Well-Known Member
Is it possible? I put some house plants in the tent with it to see if itd work but one of em looked fkd up now. Although i did transplant it from a bottle with water into soil so that may be the reason it looks so bad! Want to figure out before my herbies order arrives if i need a new light !! Thanks guys!
 

jimihendrix1

Well-Known Member
.When the 1000w HID came out in 1977-78, it was recommended for a 4 x 4 area. A 600w is best in a 3 x 3 area. Will they work in a bit larger area?? Yep. But Manufacturers like Hortilux say their 1000w HPS bulbs are recommened for a 4 x 4 area.

A 1000w Hortilux is 62w Sq/ft in a 4 x 4 area, and a 600w is 66w sq/ft in a 3 x 3.

When Gavita came out with the 1700e LED it was marketed as replacing a single ended 1000w HID in a 4 x 4 area. A 1000w Hortilux HPS is 1630umol, and a Gavita 1700e is 1700umole.

In a 5 x 5 area a 1000w HID is only 40w sq/ft.
A 600w in a 4 x 4 area is only 39w sq/ft

From what Ive read the minimum watts sq/ft for an HID is 52w sq/ft. Which would be a 4.4 x 4.4 area. Or 19.3 sq/ft. And thats minimum.

In a 5 x 5 a 1000w HID with a Hortilux HPS bulb is 64umol sq/ft.
In a 4 x 4 area its 101.8umol sq/ft.

At the equator the sun, is 2000umol sq/meter. 1 sq/m=10.7 sq/ft. At that rate the sun is 186.9umol sq/ft at the equator.

Your 4 x 4 space at optimum requires 500w, of which they dont make, and wont cover the 4ft length. I myself would try and run a 600w HID in there, and maximize the 3 x 2 area, and then whatever I got in the extra 1 foot of length is what I would get. And if the tent has good reflection, this will go a long way in optimizing the extra foot in length.

An HLG 350R would be a good alternative LED for a 4 x 2 area. $550.
 
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jb4TWENTY

Well-Known Member
48”x24”x60” is the size of the tent. I do have a exhaust fan at the top and a fan blowing air in

AND a circulation fan

besides temps what would be a negative of running this setup? by the time summer comes around i do plan on ordering 2 P2000s for this setup.
i will be running autos my first run back at growing
 

jimihendrix1

Well-Known Member
Using that much light in that area you would have to have tremendous airflow/exchange, or CO2, or you will risk over stressing your plants. And still Id say it will probably fry the plants.

1000w in a 8 sq/ft area is 125w sq/ft. And while I dont know what bulb youre using, or if Halide, or HPS. Assume its a 1000w Hortilux HPS 2100k bulb. Thats about 1630umol.
Thats 203umol sq/ft in an 8sq/ft area.
In a 4 x 4 area that would be 101.8 umol sq/ft. That would be more umol sq/ft than the sun in an 8 sq/ft area.. I very much doubt your plants would like such high umol numbers. Remember the sun is 186.9umol sq/ft at the equator.
 

coreywebster

Well-Known Member
60" is 5ft and not enough height for a 1000w hps. Even in an air cooled hood.
Infact it's a pain in the ass no matter what lighting you have. I've ran them, it can work buy it's more work.
You've got pot height, fan n filter , doesn't leave much for plant matter and space between that and light

Yeah 2x4, 4x2 whatever .
 

DarkLordMelkor

Well-Known Member
Using 1000W HPS in 5x5x6.5 tent and even with cooltube, 8" osciliating fan, 8" exhaust fan and 6" intake fan i am still having heat issues. Outside of house temp is 17C, rooms inside home temp is 22C and tent temp is 28C in general but 25C at canopy level. I hang it 100cm away from plants btw. So if you use it in 4x2 tent you must have AC for sure.

HPS bulbs are amazing but they produce so much heat. You need very nice vent system or AC. AC is must have as i said.

But then with those fans you have humidity issues. While those huge fans running in tent they suck humid air out and drying with other intake/circulate fans. Running 5LT humidifier alone is not enough for me to hit 40% RH now. When light off, 5LT humidifier can boost RH to 99%.

If you have good AC and if you can cool room temp or directly in tent to cool tent and have stronger humidifier than mine, it shouldn't be problem. But tent will be so bright to look lol.

But then strech issues starts. HPS bulbs growing them so nicely and huge.
 
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