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Is two 600w lamps too much for a seedling?
DrGr33nThumbstarted grow question 4 years ago
So I have x2 600w LED lights. Does having 1200w of light too much for a seedling? Should I just use one untill she matures abit? Thanks in advance
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MrStinkyanswered grow question 4 years ago
it is all about managing your ppfd and DLI - if you are delivering say 300-320ppfd thats alright, if you are delivering 650ppfd that is definitely not cool for a seedling and you're gonna have a bad time, m'kay?
I would say use 1 until they are mature enough to take another light, otherwise you might quickly waste €25
LeastExpectedGroweranswered grow question 4 years ago
Variables. There are more variables. The Stinkster is right...so either you have 1200w but have that light way up high to chill the PPFD down to a nice reasonable number, or you need to dim and can leave the light down a bit. DLI is light exposure across a day, so it's calculated by figuring out your plant's optimal PPFD in whatever stage (seedling), and the amount of time during the day it's exposed to that light. So a 300PPFD may be just right at 18/6 but will be too much light at 20/4 or 24.
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OGSeshanswered grow question 4 years ago
If you have the ability to dim the lamp, set the power to 20-30 percent and gradually increase as the plant grows.
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