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Issues after switching to LED lights

Rocket Soul

Well-known member
Yea definitely Ill stick with the one bulb incandescent. I might put a few more LED bulbs on for heat if they just need a few degrees otherwise it’ll have to be the heat mat. Ive done flower runs with this heat mat underneath and its fine if the plants are raised off it a bit and have a fan down near the bottom of the tent. Which I like running air under canopy anyhow
All im pointing out is that you follow temp recs to achieve plant health; your plants look pretty good to me, always listen and check on the plants first, the thermometer is secondary, not a goal in itself;)
 

chronosync

Well-known member
All im pointing out is that you follow temp recs to achieve plant health; your plants look pretty good to me, always listen and check on the plants first, the thermometer is secondary, not a goal in itself;)
Thats a great point and I totally agree!
 

chronosync

Well-known member
heres a breakdown of the feed im using lately. I use it like lucas formula more or less. With the extra calcium inputs I can adjust the N ratio of the Calnit w/o sacrificing calcium. Its basically a modified Jacks 321 formula. I use it for veg, flower, and to feed my mother plants.

Capture.PNG
 
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Porky82

Well-known member
They look over watered and the dead tips on the new growth are a zinc deficiency.
Your pH is probably to high causing the zinc deficiency and also your roots are saturated stopping uptake.
If they were mine ide let em dry right out and give em a good flush with pH at 5.7 and nutrients at normal ec.
As others have said if it's to cold they will slow right down thus using less water and becoming over watered.
 

RicoD

Member
drop your light intensity to around 60% they should perk up. thats first thing id change if you know your nutrient mix works well and dont have ph issues.
 

DokMcPuffin

Member
They look over watered and the dead tips on the new growth are a zinc deficiency.
Your pH is probably to high causing the zinc deficiency and also your roots are saturated stopping uptake.
If they were mine ide let em dry right out and give em a good flush with pH at 5.7 and nutrients at normal ec.
As others have said if it's to cold they will slow right down thus using less water and becoming over watered.
I let them dry out pretty good before i water so I know its not that, I lift the pot to check the heaviness also, but im sure I do have a PH issue and I have trouble keeping the temp above 70 I agree I think the Zinc is an issue. Thanks
 

Cactus Squatter

Well-known member
Are you running a humidifier at all? If not, run one until early flower and you’ll have a lot less deficiency issues, that was the biggest improving factor I saw when I adjusted after switching to LED.
Unless you’re somewhere it’s naturally really humid.

Also slightly upping the feed levels.
 

Ca++

Well-known member
70f ?
Heat is a plant input. It's not just their to drive water movement. It's an energy input. With HID their was usually enough, and temp concerns were almost always about it being too hot. So for a long time, it wasn't at the forefront of peoples minds. However, it is a huge growth regulator. The number one crop steerer of cannabis, it has been said.
It's quite possible, that all the saved electric from the switch to LED, will be needed for a heater. It might even need to be an IR heater. Such that the best option, would actually be a HID.


It's cold here, so I'm using a HID. As a light source alone, It wastes 200w, compared to an LED. However, if I use LED and a 200w heater, it's nowhere near as effective, as using my light as a 200w heater. My heater warms the air, but my lights warm the plants. It's really that simple. Hot air can be extracted away before it's ever done anything. While hot plants for IR heat, are hot plants. The job has been done.


There must be a way of warming the grow. Maybe it's lowering heat loss, or heat recovery of what's been extracted. Or heat inputs, such as a dehu~ as they warm and dry, and so lead to lower extract needs. I have known garage growers who profited from me chucking a blanket over their tents. Have a good think.

70f isn't something I could work with. 75f has me wondering why I'm bothering. 77f is like a minimum for me, to feel like I'm getting things done. Some strains are actually rocking at 77f, but a few more, like 80f, tends to be totally inclusive
 

Rocket Soul

Well-known member
70f ?
Heat is a plant input. It's not just their to drive water movement. It's an energy input. With HID their was usually enough, and temp concerns were almost always about it being too hot. So for a long time, it wasn't at the forefront of peoples minds. However, it is a huge growth regulator. The number one crop steerer of cannabis, it has been said.
It's quite possible, that all the saved electric from the switch to LED, will be needed for a heater. It might even need to be an IR heater. Such that the best option, would actually be a HID.


It's cold here, so I'm using a HID. As a light source alone, It wastes 200w, compared to an LED. However, if I use LED and a 200w heater, it's nowhere near as effective, as using my light as a 200w heater. My heater warms the air, but my lights warm the plants. It's really that simple. Hot air can be extracted away before it's ever done anything. While hot plants for IR heat, are hot plants. The job has been done.


There must be a way of warming the grow. Maybe it's lowering heat loss, or heat recovery of what's been extracted. Or heat inputs, such as a dehu~ as they warm and dry, and so lead to lower extract needs. I have known garage growers who profited from me chucking a blanket over their tents. Have a good think.

70f isn't something I could work with. 75f has me wondering why I'm bothering. 77f is like a minimum for me, to feel like I'm getting things done. Some strains are actually rocking at 77f, but a few more, like 80f, tends to be totally inclusive
This this this. Having grown with led, having seen how people with the exact same looking problem resolved it, this is missing temp and transpiration. All due respect, there might be other problems as well in the pot, but how are you going to solve your plants problem in the pot if it aint even drinking? And if you solve nute balance first, youll have to resolve them again once the plants are drinking properly. Drop a little incandescent like former poster if you cant get air temps up.
Extract the bottom and intract from top. Slower extraction speed.
If on a cold floor then lift the tent a bit up on a frame.
 
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aCBD

Well-known member
blowing the hot air from the top of the tent and led lights to the bottom can also help, if you don't wanna put the exhaust to the bottom. my target temperature at the highest tip of the plant with hps was 77-80f but that's like the minimum now with led.

great thread with a lot of useful tips and information, it's like a how-to-led guide on just a few pages 👍
 
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phunkeeboodah

Active member
one week into november and it's shorts and t-shirt weather here and dark at 5:30pm, so still using the led. f the oiligarchy

i have the hid and led bars set up together so i can switch or combine them on the fly
 

yahooman

Well-known member
Veteran
This this this. Having grown with led, having seen how people with the exact same looking problem resolved it, this is missing temp and transpiration. All due respect, there might be other problems as well in the pot, but how are you going to solve your plants problem in the pot if it aint even drinking? And if you solve nute balance first, youll have to resolve them again once the plants are drinking properly. Drop a little incandescent like former poster if you cant get air temps up.
Extract the bottom and intract from top. Slower extraction speed.
If on a cold floor then lift the tent a bit up on a frame.
Yes,it seems like toomuch work for a hobby grower on a budget
 

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