How high from top of the plant my 1000w HPS must hang?

[Xan2]

I am building a 5' wide, 4' deep, 5' high and i am wondering if 18 inches is enough between the bulb and the top of the plant?

Thanks.

 

[panhead]

Nobody can tell you an exact distance nor can they even get a rough estimate that means anything in your grow op,there are too many factors unknown.

The only fool proof way to keep any hid light at a safe distance yet still have it as close to the canopy as possible is to measure temps at the canopy.

Get an old style mercury thermometer & hold it right at the top of the canopy,digi thermometers are unreliable in my experience & can give wildly different temps by a simple movement,then raise/lower the light until the temp is where your comfortable with it,i keep my lights where the canopy temp never gets any hotter than 80 degrees max.

 

[SOMEBEECH]

If you only have 5ft tall as high as you can get it! Then like pan sais take temp! I would say no to the 18inches.

 

[Xan2]

What is the ideal temp to read on that thermometer on top of the colas?

 

[Hank]

Indoors i would think 90 degrees be pushing it. I like to range my temps from 75-80 degrees.

-Hank.

 

[Cr8z13]

What kind of ventilation will you be using? That 1000W light is going to get hot as hell in such a small space. I would think a Cool Tube or another air-cooled hood is an absolute must.

 

[mygirls]

I am building a 5' wide, 4' deep, 5' high and i am wondering if 18 inches is enough between the bulb and the top of the plant?

Thanks.

my plants are right in the hood with my 1000wtt. but i have a 20 inch box fan that hangs at light level to blow the heat away from the top of my plants. been doing this for 2 year and have not burned a cola yet. i run it on high when light is on

 

[Xan2]

What kind of ventilation will you be using? That 1000W light is going to get hot as hell in such a small space. I would think a Cool Tube or another air-cooled hood is an absolute must.

My 1000w is on a basic reflector. And i installed fireproof gypsum on the top of the grow box.

I have a fresh air intake 70CFM of 3" tube
Exaust is 100CFM of 4" tube
I know 100CFM is not much for exaust but i just build the room and don't have any flowering right now so might consider a 100$ inline fan to add to the exaust...

A fan will be pointing directy at the bulb to throw away the heat and another fan would keep the air moving between the bulb and the top colas.

Is that good enough?

Thanks.

 

[Cr8z13]

I sure hope so, but I have my doubts. The only way to tell for sure is to fire that light up for a few hours, sort of like a dry run. If your temps get hotter than 80 degrees you're going to need a more agressive cooling plan. Another thing, try and take the temperature about 2ft from the bulb. That reading will be about where your canopy will be. You can get it closer with a better hood, but let's see how things go for now.

 

[Xan2]

I sure hope so, but I have my doubts. The only way to tell for sure is to fire that light up for a few hours, sort of like a dry run. If your temps get hotter than 80 degrees you're going to need a more agressive cooling plan. Another thing, try and take the temperature about 2ft from the bulb. That reading will be about where your canopy will be. You can get it closer with a better hood, but let's see how things go for now.

Thank you much appreciated, will try the light once the room will be done, hopefully tonight. I will let you guys know how things goes.

 

[jnuggs]

I have a question, if someone will oblige.

My flower chamber will be 6' wide, 4' deep, 6' high(all INSIDE measurements). Should I run 2x600w, or 2x1000w? My exhaust for this chamber would be a 500 CFM S&P 8" inline fan. Would that be able to cool this?

 

[leggoeggo]

 

[Cr8z13]

I have a question, if someone will oblige.

My flower chamber will be 6' wide, 4' deep, 6' high(all INSIDE measurements). Should I run 2x600w, or 2x1000w? My exhaust for this chamber would be a 500 CFM S&P 8" inline fan. Would that be able to cool this?

2x600w should suffice. Cool Tube reflectors would be good too. You can easily connect them to your fan, but you'll need an 8" to 6" fitting because the Cool Tube has 6" ports.