Too much light for seedlings?

Hi all!
This is my first post about my own grow! So as most new folks go, I’m sure I’ll have lots of questions.
My first one is about light.
Have 2 seedlings, about a week in cups.
2x2x4 Tent
Light: HL Diablo 200 about 22” from the seedlings.
I’m concerned that is too much light for them.
And thanks in advance for the help!

A good bit of light provides for nice, compact plants. Place the back of your hand at the level at the height of the seedling. If you can feel the heat on the back of your hand, then the light is too close. All else is fair game, but be aware that a light that is placed too high will lead to the seedlings stretching, which is not what you want.


Great light, I had to hang mine at 36” and dialed down as low as it would go for the seedlings. My DLI was 18-20. I also like to use a 24” T5 fluorescent light :love_you_gesture:


Thanks for the quick reply!
The back of my hand is warm but not hot or uncomfortable.
My concern is because I’ve heard to set your light to something like 60% to start seedlings. Unfortunately I don’t have the ability to dim my light at the moment
I have the Photone app but I’m not completely sure what I’m looking at with that.

Great take on lighting. I didn’t think of it. Hope you find this helpful.

PPFD may not mean much to you, but the relative comparison might be. General guidelines are:

Seedlings: 300 PPFD
Veg: 600 PPFD
Flowering: 900 PPFD

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Appreciate the confirmation. I couldn’t remember the PPFD off the top of my head. I’m use both and the back of my hand as well :love_you_gesture:

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Woah…. You guys lost me a bit there.
I have the Photone app. Can someone tell me what I should be measuring? And what that measurement should be?

Search the site for Photone app. You will find people who have done the work with the app.

The DLI thread has a lot of discussion of the app too. You can search withing that thread to find app info.

I’ve never used the app, so I can’t help you myself.

It’s simple, just make sure the setting is on the time interval as in 18/6 or 12/12. You’ll need to cut a strip of printer paper about an inch wide and long enough to wrap around the phone covering the camera lense. Place it at the top of your plants and check DLI or PPFD. I set my height at 30” for seedlings, 20-24 for veg and 18-20 for flower and dual the light intensity up or down for adjusting the DLI :love_you_gesture:

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Not that I am an expert in this but have had 2 successful grows.

I only go by lux since I can measure on my phone and easily calibrate it to the full sun. 90,000

Seedlings: 5,000-7,000 lux
Vegetative: 8,000 - 15,000 lux
Flower: 16,000-35,000 lux

Has worked decently for me

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Ooo…. Just checked DLI. Reading was 40.
As I feared…. I’m sorta cooking them. :face_with_diagonal_mouth:
Since I can’t get much further away, I think I need to figure out a dimmer

Pics would help and yes that’s. Little intense for seedlings :love_you_gesture:

Here’s photos. The first one is very squatty. Which made me think it was getting too much light. The second one looks a little better.
Thanks for the tip on the manual dimmer on the control box. Yes, I just checked and adjusted. I got it to 320 PPFD. Which I think is where I want to be!


Nice looking baby

Ur plants look great .this is what i do i hang my light about half way mark in the tent i set my light to 40% i havent had any problem with doing this

Perfect :love_you_gesture: