400 hps mh?

pingweed

Active Member

Sep 21, 2007

• #1

How far should you have a 400 mh or hps from top of plants?

 

potroast

Uses the Rollitup profile

Sep 22, 2007

• #2

With a good horizontal reflector, a 400w should be 15-20 inches above plant tops. It will light an area about 3ft x 3ft.

HTH

 

nongreenthumb

Well-Known Member

Sep 22, 2007

• #3

It all depends on what stage the plant is at though, if its just a seedling that could be a little intense for them.

 

spliffy777

Well-Known Member

Sep 29, 2007

• #4

my seedlings suffered when i had my hps that low 2 um ,i lifted um up 2 24 to 30 inchs away 2 start off