Is too much light an issue?


#1

I’m setting up 4x4 tent so I went shopping on Amazon for good lighting solution. I found a used (condition as new)
LED 1800watt/6-300watt COB full spectrum light for less than $100. I jumped on it.
What is a good height above flowers?
How careful do I need to be?
I’ve read a lot about too little light, is this over kill?


#2

I’m not sure what the max light you can have is, I’ve run as much as 70watts/ft². You can put your lights to close also where it will hurt your plants but I don’t know the necessary COB distance for 300 watts

@dbrn32
@Donaldj


#3

It isn’t about the lights watts it is about the directed intensity cobs and LED’s are more directed focused and require some distance to diffuse and blend. I have mine at about 18" for flowering


#4

I concur with what @Donaldj and @TDubWilly are saying. It’s hard to suggest a blanket measurement based on watts. I would say on most accounts you’ll have plenty of light. If they’re running pretty efficiently you could probably do well with four of those fixtures.

I would probably hang four of them about 24” above canopy and kind of thumb eyeball the coverage and see how it looks. If it looks like you’re getting pretty good coverage run them there for about 5 days monitoring plant response. They’ll usually try to drop leaves away if it’s too much or you’ll see some burn along edges. If they like it, you’ll usually see them perked up towards the lights. Then you can lower a few inches and repeat.

Hopefully that helps!


#5

Thanks for feedback. I’ll use 2 foot rule with follow up. I want to make sure I described light correctly. It’s one 1800 watt light. The 6 COBS are built in.


#6

Oh, is it available on Amazon? If it is, can you link it please?

I’m only asking because chances are it draws a lot less power than that, and you may need a couple of them to flower that size space well.


#7

Here’s the link. There’s a few more left. Let me know what u think? First time I’ve uploaded link. Wish me luck…


#8

Link it’s working 4 me. LMK if Link works?


#9

From the link that light puts out 300 true watts from the wall. In a 4 x 4 tent you need 800 true watts. Therefore you would need 3 of those lights for full coverage.


#10

Gotcha, thanks for info. Mo-Money Mo-money


#11

HJL, can you give me the formula you re using to get true watts. It’ll help me shop for more light.


#12

35w sqft veg 50w+ for flower
Most manufacturers list true watts in description of their lights
Simple break down is for 4’x4’ tent 16sqft you want lights to sit in range of 600-800w 35x16=560 50x16=800
you can flower under 35w but yields are reduced


#13

Sorry, I didn’t see your post until now. Next time tag me and I’ll get a notification.

Here is what stands out to me, that’s very very poor efficacy for a white led.