how close can a 400 watt hps be to weed plants ?

[almightyfinesse]

i have 2 ak48 weed plants and one is getting taller by the day becuase it flowering right now and the light is 5 inch away from the top but it not doing any damge to it but i saw a hps light distance chart and it said 5 inchs is too close, i have a 400 watts hps air cooled hood

 

[amgprb]

 

[amgprb]

Optimal distances:

400 watt = 12"

600 watt = 18"

1000 watt = 24"

(From canopy top)

* this is just a guide line and starting point, you can tweek the distance based on strain, heat, and other variables. Start with this guideline, and make adjustment daily to find YOUR optimal distance. Go slow so as not to cause stress, making 2" adjustment in distance at a time in either direction.

 

[*BUDS]

Depends on the current temp. If it goes up and the plants are too close they will burn. Just use cooltubes to get them as close as possible without burn, which can cause major issues.

 

[almightyfinesse]

my plants are 5 inch away from the light bulb and it not burning them

 

[Blindnslow]

I run my 400 @ 12" away during veg and 1/2 of flower. The second 1/2 of flower i get the top colas as close as 6" with no burning or ill effects. That's with a glass enclosed air cooled hood. My room temps are always in the lower- mid 70s during light on.

 

[ODanksta]

lol, he said weed plants..

 

[almightyfinesse]

I run my 400 @ 12" away during veg and 1/2 of flower. The second 1/2 of flower i get the top colas as close as 6" with no burning or ill effects. That's with a glass enclosed air cooled hood. My room temps are always in the lower- mid 70s during light on.

thanks

 

[BeastGrow]

at least one span of a hand

 

[blackrecluse]

start tying them over a little. 3 inches is way too close. becuase the next time you check them it could be touching and or on fire. 6-4 inches is perfectly fine. If its air cooled, I bet it could touch the glass.