just got new 400-watt hps. distance?

how close should it be?

put a few small computer fans blowing on it, or cooltube etc, if it doesnt burn your hand when u put your hand at plant level its fine.. id say 6+ inches be fine, if it doesnt burn its ok..

6in? i burned my plant with from farther than that with cfl's though

lol, ok nevermind... go any distance u want the closest that doesnt burn your hand... where ever that distance is that is what u want

kinda simple.. get some fans..

Hang a thermometer from it. When it stays at a happy temp , thats your distance.

good point. you can grab a thermometer that doubles as a humidity reader from lowes for like $3. i just picked one up on saturday and i just stick it right next to my pots to see the temp and humidity they're getting. cost efficient too

initially you probably want to keep the light about a foot to a foot and a half away from your plants if the temp is at 75-80, the warmer it is in your room the farther away the light should be. If the temp gets to be about 70-75 i would have you light as close as possible with out heat stressing the plant.

i dont have a gud enouf fan for that. i just have a lil heater in there thats set on fan to bring in colder air from the room

Cooler temperatures produce denser buds, fact.

its not too hot right now so im leavin it. im just trying not to catch the curtains on fire

so yeah as long as your hand feels confortable under the light at the distance your plant will be away from the light than the plant should grow fine but if you rin out of space you might risk burning your plants, you should be fine though.

LOL...You guys are funny. Hang it a good foot or two from the tops of your plants. As they get older, they can handle it closer.

With a cool tube you can get alot closer but then you are light bleaching them. Its always a toss up

~Boneman

i put a big ass fan one them. on the lowest setting its still reallystrong so i think the are fine

sittinherebored said:

i put a big ass fan one them. on the lowest setting its still reallystrong so i think the are fine

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I just bought a 150 watt hps light and put it in my little grow area and the plants turned yellow. I took it out because I couldn't get it high enough and put in four cfls which are correcting the problem. It didn't feel too hot with my hand underneath. Could the plants been too young to handle the light? It seems like thats what was said. How old should the plants be before putting them under the hps. Thanks.

I dont think your plants were too young you probably just had the light too close.

a couple different factors, but in general...

(1) 400 watt hps @ 2.25 ft above the canopy will put off 10,000 lumens in each square foot.

this is enough for a 5'x5' square, giving each plant 12", while distributing 10,000 lumens evenly through the space.

this is perfect for flowering, each plant needs 10,000 lumens for flowering, if you lower the light any more, then it will be recieving way more lumens.

Ya, you're probably right, thanks. I'm trying to figure out a new location, I only have about 2 feet tall by 2 1/2 feet wide in the little space I have them in now. I'm scoping out and trying to find a little cabinet of some sort. This growing is so much fun, and addictive, I love it. Been reading about supercropping, how interesting is that?

ive had a 1000watt 4 inches from the tops of my buds and never had burning problems. i think as long as you have good vent and blower you be fine.

right now we have a 400 watt hooked up to a blower that could easily cool 2-3 1000's and the glass on the bottom of the hood is cold to the touch.

AK47StEvY said:

initially you probably want to keep the light about a foot to a foot and a half away from your plants if the temp is at 75-80, the warmer it is in your room the farther away the light should be. If the temp gets to be about 70-75 i would have you light as close as possible with out heat stressing the plant.

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was wondering, is this any aged plant or can plants be too young for this much light?

sorry for asking the same question as before, i did get the answer. now have a 400 watt hps in a small grow tent and temps get very high in here now, i'm installing an exhaust. really wondering about how well the led lights do as the size and low heat is nice.