Hps Light:distance From Plants?

**ManInTheShed** · 02-21-2007, 12:32 PM

my hps just arrived in the post today, very happy lol! gonna have some bushes soon. Up until the light arrived in the post i had been using floros, and i kept them very close. But now im not sure how far away the hps has to be. the plants are pretty small too at the moment.
ANY info on 400wat hps growing in a tent would be great. thanks for any help.

**bullmoose77** · 02-21-2007, 04:09 PM

Roughly 18 inches, potentially a couple of inches more or less depending on your exhaust set up.

**TillthedayiDIE420** · 02-21-2007, 04:18 PM

if you have a Glass incased HPS bulb cover.. with exhuast... u have have it 10 inches or closer they can be touching the tops of the plants... u just gotta check if it burns you... and if you dont have a glass inclosed then it needs to be 18 inches away because its hots.

**VictorVIcious** · 02-21-2007, 06:46 PM

Start at eighteen inches and move it down a few inches a day until it is within a foot of the canopy. The plants will grow up to meet the light and you don't want them to stretch too much.

**TillthedayiDIE420** · 02-21-2007, 07:22 PM

if there is no glass cover you dont want them 12 inch's... HPS get very hot...

**VictorVIcious** · 02-21-2007, 08:50 PM

depends on the hood and the ventilation. 400 watt don't get that hot.

**rezo** · 02-23-2008, 03:37 PM

what about a 1000w w/ glass

**freddog23** · 03-21-2010, 09:52 AM

ive read in the jorge cervantez biblethat for seedlings 3 to 4 feet. once in veg im not sure i have the same question. but for seedlings 3 or 4 feet. i preffer 3.

**CLOSETGROWTH** · 04-26-2010, 06:38 PM

Originally Posted by freddog23

ive read in the jorge cervantez biblethat for seedlings 3 to 4 feet. once in veg im not sure i have the same question. but for seedlings 3 or 4 feet. i preffer 3.

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