400 hps lights how close to plant Help

[Madshotz]

I just changed ova to HPS I have plants that are starting to flower now how fare away should the lights be

 

[JBonez]

near the base of the bulb is where the heat is most intense on my 400 hps, but i have a cooltube with a 300cfm fan pushing through a carbon scrubber.

so i am about 3 or 4 inches, one plant has light burn, but the rest are fine.

here is what a 400w is capable of. Nirvana Bubblicious.

 

[pcduck]

Place your hand at canopy level. Lower light till you feel heat on the back of your hand and stop. This should be the heighth that you want to have. 8" to 10" air cooled even closer

 

[JBonez]

Place your hand at canopy level. Lower light till you feel heat on the back of your hand and stop. This should be the heighth that you want to have. 8" to 10" air cooled even closer

:yeahthat:

 

[Motor City Madman]

I have a air cooled 400 watt HPS 300cfm fan pulling cool air from the basement and venting to the garage. My plants are 4" from the light.