How far should I have a 400w light from new seedlings?

Hackerman

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I planted some seeds Friday. Nothing has popped up yet but when they do I don't want to burn them.

How far should the light be from the seedlings

I am using an air cooled, 400w HID.

Thank you
 
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You should basically have any hid light far enough from your plants that the back of your hand is warm but not hot. If the back of your hand becomes uncomfortable you should probably raise the lights. Pretty sure that rule does not apply to LED lights though. Pretty sure they can do damage without the heat factor if too close. Jmo
 

Hackerman

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The light is about a foot away. Maybe a little more.

It definitely doesn't feel hot when I put my hand next to the planter but the thermometer sitting next to it reads 81F.

I may raise it a tiny bit more.

P.S. I was just looking at them and I see a tiny sprout trying to break through the soil. :)
 
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If they are seedlings than disregard everything I said. I guess I am baked and thought these were plants in veg. Seedlings need more care IMO. Especially under HID lighting. I veg under HO T5's and can get them down close. If your temps at soil level are that high back them off a bit till they get a bit older and used to the light. Jmo
 
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A foot or so is probably good. Seedlings tend to like it a bit warmer. Just make sure that they do not dry out. It isn't just the heat, the light intensity can seem to just suck the moisture out of the leaves sometimes. I would check them a lot at first. It has beed many moons since I have started seedlings under a MH.
 

Hackerman

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I look in on them about every 2 minutes or so. LMAO

Last night we had a power outage from a storm and I sat next to them with a flashlight and shined the flashlight on them and sang love songs to them.

This is my first time with hybrid seeds so I am a little anxious. LMAO
 

Track

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If there's a thunderstorm where you live, I'd chance to say that it's probably not too hot.

But when the heat does return, come summer, I'd hoist those lights higher.

The hand underneath the light method works well, but you should still check in on them daily until you can be sure there is no light burn.
 

Hackerman

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Thanks bud. I check on them often. I'll watch for any burn.
 
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