HLG Light usage

HitemwiththeHine

HitemwiththeHine

Well-Known Member
Also, if you have stretchy seedlings it's ok because you can transplant them and bury the stem. Some people even plan on doing that and they score the main stem as they bury it so new roots can grow.
 
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GreenPeace22

Active Member
HitemwiththeHine said:
20 on till about 2 weeks, 18 on in veg. If I'm going to flower in the same tent, I'll adjust down to 17,then 16,then 14 in the week before flip. You don't have to do that, it's not a hard rule for me either, I just like doing it.
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Haha, thank you very much man! But light schedule means hours of light and darkness :D. 18/6? 20/4 ? 24/7? Which one are you using?
 
U

unfiltered

Well-Known Member
HitemwiththeHine said:
Start at 24" on lowest power and watch the edges of the leaves. If they start to curl in even slightly back it off.
Click to expand...
I have 5 QB288's. I have burned the crap out of my plants, seedlings, veg, and flowering using the recommendation PPFD value from HLG website. BTW, I first used the Lux phone app to convert to PPDF. Still, my plants got burned! I will never go with some rigid number or standardize system.

Listen to what @HitemwiththeHine suggested. Your ultimate goal is the keep the plants such that they would pray or angle up to the light at all time and stages of growth. Whenever you see any sort of droop, tip curl, and yelllowing at the top of the canopy, then the light is too intense. Remember, the light is the driver that dictates almost everything such as nutrient uptake, water uptake, etc. Well, VPD is another thing that also dictates growth. What you think is deficiency could actually be the light being too intense. With QB's you need to increase Ca and Mag by a large amount. As you grow, you will know the science behind that. Here are some clues...Mg (and Ca) uptake are related to chloroplast and is related to photosynthesis and thus related to how intense your light is.

As you see below, the Lux app on your mobile phone is actually acceptable for measuring light intensity and use as reference. You can convert the lux value to ppfd. I also bought a PAR meter to compare and using the lux value converted to PPFD is quite close and acceptable to the PAR meter. Here's the Lux to PPFD online conversion. https://horticulturelightinggroup.com/blogs/calculators/converting-lux-to-ppfd

Here's what I do.

- With all stages of growth, start by hanging the light at least at 24" or even 30" above the canopy.
- Use lux app (or PAR meter if you can afford it) on your mobile phone and use the recommended PPFD and DLI to start off. Use the lower range first.
For example, if HLG recommends under 100 PPFD for seedling/clones, I would start at 50 PPFD by dimming or raising the light, and watch the plant.
- Increase PPFD by a value of say 20 PPFD every week or something (You need to work out your own system and method). Again, watch the leaves and make sure there's no droop, tip curl, or yellowing.
- Keep increasing the PPFD until you start seeing light stress and if so, then back it off immediately. If you burn your plant, it will take about a week to show as interveinal chlorosis (yellowing) and then advance to necrosis (brown burnt spots). This is related to Ca and Mg are being utilized under intense light. Remember, always keep your plant/leaves in such condition that they always pray. Praying plants are very happy plants that are growing at optimal level. Karl Kushman measures his plants' vigorous growth level by how much they pray or angling up. If the leaves droop = bad. If the leaves are just flat = you can do better. Give them less intense light and they will pray.
 
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R

Ryante55

Well-Known Member
Nizza said:
Well I think someone with the right experience could write a tutorial on how to properly distance the HLG quantum 288's. I bought alot of them and if i put them too close it sucks to see what happens after sometimes
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What current are you running at? Maybe actually give some info. Don't buy a diy light if you can't figure shit out yourself.
 
R Burns

R Burns

Well-Known Member
GreenPeace22 said:
What wattage u using for seedling and early veg? Seedling is what concerns me the most. I don't want it to stretch, neither to get burnt, just enough for her to reach peak performance.
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Whatever the lowest is. Dialed all the way down for the first 10 days or so. Couple of days at around halfway and then full on.
 
PURPLEB3RRYKUSH

PURPLEB3RRYKUSH

Well-Known Member
Download a PAR app on your phone, compare with light for accuracy, some apps work good for light readings or by a lux metre as stated above or easiest method read yah plants
 
G

GreenPeace22

Active Member
unfiltered said:
I have 5 QB288's. I have burned the crap out of my plants, seedlings, veg, and flowering using the recommendation PPFD value from HLG website. BTW, I first used the Lux phone app to convert to PPDF. Still, my plants got burned! I will never go with some rigid number or standardize system.

Listen to what @HitemwiththeHine suggested. Your ultimate goal is the keep the plants such that they would pray or angle up to the light at all time and stages of growth. Whenever you see any sort of droop, tip curl, and yelllowing at the top of the canopy, then the light is too intense. Remember, the light is the driver that dictates almost everything such as nutrient uptake, water uptake, etc. Well, VPD is another thing that also dictates growth. What you think is deficiency could actually be the light being too intense. With QB's you need to increase Ca and Mag by a large amount. As you grow, you will know the science behind that. Here are some clues...Mg (and Ca) uptake are related to chloroplast and is related to photosynthesis and thus related to how intense your light is.

As you see below, the Lux app on your mobile phone is actually acceptable for measuring light intensity and use as reference. You can convert the lux value to ppfd. I also bought a PAR meter to compare and using the lux value converted to PPFD is quite close and acceptable to the PAR meter. Here's the Lux to PPFD online conversion. https://horticulturelightinggroup.com/blogs/calculators/converting-lux-to-ppfd

Here's what I do.

- With all stages of growth, start by hanging the light at least at 24" or even 30" above the canopy.
- Use lux app (or PAR meter if you can afford it) on your mobile phone and use the recommended PPFD and DLI to start off. Use the lower range first.
For example, if HLG recommends under 100 PPFD for seedling/clones, I would start at 50 PPFD by dimming or raising the light, and watch the plant.
- Increase PPFD by a value of say 20 PPFD every week or something (You need to work out your own system and method). Again, watch the leaves and make sure there's no droop, tip curl, or yellowing.
- Keep increasing the PPFD until you start seeing light stress and if so, then back it off immediately. If you burn your plant, it will take about a week to show as interveinal chlorosis (yellowing) and then advance to necrosis (brown burnt spots). This is related to Ca and Mg are being utilized under intense light. Remember, always keep your plant/leaves in such condition that they always pray. Praying plants are very happy plants that are growing at optimal level. Karl Kushman measures his plants' vigorous growth level by how much they pray or angling up. If the leaves droop = bad. If the leaves are just flat = you can do better. Give them less intense light and they will pray.
Click to expand...
Thank you very much for your time! My problem was that the seedlings' cotyledons were getting yellowish and then the first set of true leaves burnt. At first I thought it was the medium being too hot, but I tested it and the EC was right below 0.4. I was using my light at 20 inches dimmed to 75W. Maybe it's still too much, and I'm stating to think about what you said : too much light, make it take up nutrients too fast, and burns, even if the EC is good. Could be one theory, I'll try dimming the light even more, to 50W or something, will see what happens...
 
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GreenPeace22

Active Member
Ryante55 said:
He answered your question pretty well all the info you want is in the post can you read?
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Yes, friend, I can read and speak, even if english is not my foreign language. When he said 20 and 18 I thought he was talking about inches for the light height. My bad for not paying enough attention, I'll admit it. Sorry that I'm not perfect. Also, thanks for your time and advice, I appreciate it!
 
Moflow

Moflow

Well-Known Member
GreenPeace22 said:
So, I am growing one auto in a 2 by 2 feet space, under a LED HLG 135W Rspec (3500k), which can actually pull up to 162W
at maximum driver capacity.

I want to know, (because HLG gives 0 info), which are the hanging heights and the corresponding wattage
for each stage of growth, for example : Seedling - 60inches - 100W, veg :.... and so on...

It doesn't have to be specifically for this model of light, it can be something general for LED lights of this power,
I'll adjust on the go, I want to know what works in general, with the best results for the best efficacy, without
stretching or light burn or anything damaging.

Thank you!
Click to expand...
For flowering 18" ...... maybe even 16"
18in-PPFD-1-1.png
 
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