I think that if they are responding good right now with the light 6 inches away then you are in fair shape. One thing to remember is, with the light that close it isn't able to cover more than probably a 2x2 area IMO, so you may want to put it at about 8 to 10 just to get a little more coverage if your space is bigger than 2x2.
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BlueBear Reviewed by BlueBear on . Lighting Question My girls are in the 2nd week of flowering. I am concerned about how close I should let them get to the light which is HPS 400W. I've been lsting and have chicken wire 6 inches below the light. I have fan blowing directly on the light to help cool the plants down. Right now I don't see any damage to the tops since 3 tops are at the chicken wire. What should I do? Rating: 5