Lighting What's the best lighting cycle for autos - 24/0, 20/4 or 18/6

What is the best lighting cycle for autos?

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Do you have the internal dimmer or external? I find the A drivers with the internal POT to be a total pain in the ass, and the slotted stem is plastic, and very easy to damage. I'd only use them on lights I had no plans to dim.... or to adjust no more than a couple times. But that is the driver most often supplied with kits.


Couch_Lock said:
My HLG no longer dimms, its worn out. I kinda feel sorry for my baby autos, they gettin pelted 24/7

Weather forecast is warmer next week, I hope to be able to shut down 3-4 hours a day. I keep the light a good 35 to 39 inches away but all this brightness doesn't seem to help the vegging. That period is almost over, Im seeing tiny prebudlets......oldest plants are 25 days old, two of them are 22.

The Timber 2 VL is not enough wattage by itself.....and the CMH seems to go through bulbs like crazy, I'd rather not use that. Next grow I'm gonna have to buy a few Phillips cmh bulbs again. Beats droppin another $700-900 on a light.
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External, Pop.

Was working on it this morning, I have gotten it to finally move again. But the damage is done to one of my 4 plants........it may not make it. Not sure if it was excessive DLI or the fact I defoliated all four 3 days ago.


I'll add a pic to this post later on.

I'm over top of the affected plant, top right among my plants. Its 24 days old and is looking rough.




Might just toss the thing, its a Roc Bud. Never had branches that looked strong like all the rest always do.


An 11 inch plant with 14 sets of leaves.
 
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pop22 said:
I'll give you a deal when I'm done with the one I plan to order next week. My current light are long term so once I have the data I need I won't need the meter again.
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I appreciate that!
 
Chilli said:
Apologies, as this must have been asked many times before but a quick search on here resulted in nothing.

As the title says, what is the best lights on/off cycle for autos (24/0, 20/4 or 18/6 etc), or does it change dependent on what stage of growth the plant is on (germinating/veg/flower)? Currently I have some 1 week old seedlings on 20/4 (lights on/off), as I'm guessing the 4 hour dark period will help with the root development and the 20 hours light will help leaf development.
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Wow, no matter where I search I get the same answer, there is no real consensus on what is the best light cycle. Ive had bigger buds with 24/0 light then 18/6. But I really can't say definitively because there are so many variables. I dont grow the same species of autos so until I do, I can't judge the difference in light cycle grows. What is more important to me is to daily observe my plants. Depending on the type LED lights you use some will be much more effective on a longer lights on periods.
I'm more concerned with having enough quality lights.
 
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    Nosias

    Nosias

    points: 10
    so true, listen to your girls.
Camhar said:
Wow, no matter where I search I get the same answer, there is no real consensus on what is the best light cycle. Ive had bigger buds with 24/0 light then 18/6. But I really can't say definitively because there are so many variables. I dont grow the same species of autos so until I do, I can't judge the difference in light cycle grows. What is more important to me is to daily observe my plants. Depending on the type LED lights you use some will be much more effective on a longer lights on periods.
I'm more concerned with having enough quality lights.
Click to expand...
I have a 5x5 with 450 watts and I did good. Then much later I added an additional 250 watts and the girls all got fat and happy. It is the light then your care and love.
 
I run 24 on with my autos and photos in veg I must add my light is not the most powerful (4 qb132) which doesn't give much ppfd unless dropped real low. Less than 10 inches. I use rootbuilder pots which give great root growth and my autos love it . Too small to finish in so I uppotted after 2 to 3 weeks into 5 gallon grow bags filled with about 4 gallons of medium. Started Aug 3rd. Candydawg auto from seedstockers
IMG_20210913_160654_185.jpg
 
Nosias said:
I have a 5x5 with 450 watts and I did good. Then much later I added an additional 250 watts and the girls all got fat and happy. It is the light then your care and love.
Click to expand...
Thanks for your input. So, I'm still a little confused about LIGHTING. I dont have the extra cash to replace the lights I already use. When we, me especially, look to enter into growing there are so many questions that need to be answered. Think about it, the list is pretty long. I won't get into the struggles of a first timer like myself.
I started growing in June of 2019. I bought my tent, ventilation system, and after a lot of searching I bought 2 Viparspectra p1000 lights. My tent is a 2x4x5. At that time I didn't really know anything about how to choose the lights best for my situation. I read on the forum that wattage can be determined by multiplying the sq ft of the tent x 30 or 40, and following that it looks like I am lacking. Im pretty sure that I should upgrade my lights. I feel really dumb about this and would love to hear for anyone with suggestions.
 
Some use 24/0, some use 20/4, some use 18/6… most of that depends on cost of electricity. That is why we look for the most efficient lights possible. When it comes to your space, something in the so series of Mars hydro would work… maybe SP3000! 300 watt. Mars hydro sells them for a 2x4 space
 
Jpkindbud said:
Some use 24/0, some use 20/4, some use 18/6… most of that depends on cost of electricity. That is why we look for the most efficient lights possible. When it comes to your space, something in the so series of Mars hydro would work… maybe SP3000! 300 watt. Mars hydro sells them for a 2x4 space
Click to expand...
My choice is 20/4 cuz I believe they need a little rest…
 
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