Why do LED grown plants show deficiencies vs outdoor?

I had this plant, bubba's gift that I grew from a feminized seed under blurple lights about 2 years ago. The plant was fine the first time around, but after I cloned it, it started showing a lot of problems. Red, woody stems, strange colored leaves that looked like phosphorus deficiency but hard to tell because the leaves were also a lot darker than a normal plant. The leaves are also wider under blurple in my experience (because of more red?) than normal as well but that doesn't have much to do with my question/story.

Anyway, I put a clone of this plant outside recently and it's completely cleared up. No more red/purple stems, no strange leaf colors, nothing. It looks as good as when I put it out from seed and it's in the same medium and receiving the same nutrients. I haven't tried this under my cobs yet but even under my cobs I notice more red of the stems that I have in there. I have heard people say that led's make plants use up more magnesium but with my Bubba, it was more than that it seemed. I tried upping my cal mag, I tried epsom salt, nothing would clear it up under the blurple lighting.

Another observation under my cobs, now my leaves are much smaller width, completely opposite of blurple (3000k 90 cri mixed with 3500k 80 cri). Also the serrations look very pronounced, which I understand to be a product of more light. At least that's what I read about trees, that higher up the leaves will have more pronounced serration because they are receiving more light. That doesn't explain the small width of the leaves though as far as I know, just the pronounced serration.

I'm asking a few different questions here I guess as I'm trying to learn more about how light affects plants but if you skip everything else, I'm wondering if anyone has any theories regarding my Bubba's Gift plant. I can post pictures if people want as well. Not even sure anyone's gonna read this, just some stuff that's been on my mind for a while and hoping to probe some more experienced minds for some general information to point me in the right direction. I've read a lot of threads here about spectrum, but never seen it explained really why led's (or maybe just the specific spectrum?) might create deficiencies.

What is the air like in your indoor grow?

It's in two tents in one room in a basement with the door open. I have an intake and exhaust fan in the flower tent and only an exhaust fan with passive intake in the veg tent. Air is filtered throughout the house and the temp is about 68, rh I think is about 50 at that temp (maybe lower). It does have an air vent in the room (in the ceiling) but no windows. I vent air out of my flower tent outside of the room. I've thought that maybe there isn't a lot of co2 or something in the air in the basement but could that really cause all these problems?

Well, two years ago when you grew it was fine so what variable may have changed since then? What medium were and are you growing in now Vs. Then? But I grow under various low power lights as a mix together such as 6 tubes T12's and I go from Daylight to Soft white and cool white, CFL's I do the same, and a supplemental 70W HPS, so I have a mix of lighting but all LST with all light close 2-6" away from tops and I also get purple lines up the fan leaf stems 90% of the time but all growth though not as full all looks healthy but as you noticed when I grow outdoors MOST of my plants had none of those purple leaf stem lines but a few in other locations did outside. Hard to say I think lots of people talk about this and some say it could be a deficiency and others think its a trait; pictures might help.

Halfandhalf said:

It's in two tents in one room in a basement with the door open. I have an intake and exhaust fan in the flower tent and only an exhaust fan with passive intake in the veg tent. Air is filtered throughout the house and the temp is about 68, rh I think is about 50 at that temp (maybe lower). It does have an air vent in the room (in the ceiling) but no windows. I vent air out of my flower tent outside of the room. I've thought that maybe there isn't a lot of co2 or something in the air in the basement but could that really cause all these problems?

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Way too cold. Your plants metabolism is almost off if it's only 68* at lights on. And with no IR heat in the beam via LEDs, its way worse than 68 in sun or under sodium. 75* at the lowest. You'll have better results closer to 82-85*.

Greengenes707 said:

Way too cold. Your plants metabolism is almost off if it's only 68* at lights on. And with no IR heat in the beam via LEDs, its way worse than 68 in sun or under sodium. 75* at the lowest. You'll have better results closer to 82-85*.

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What led spectrum are you recommending for growing plants that have the same characteristics as Sun grown plants?

OneHitDone said:

What led spectrum are you recommending for growing plants that have the same characteristics as Sun grown plants?

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What he was saying as far as how and sunlight is that they both produce infrared light, which heats the canopy above the room temperature. LEDs do not produce any infrared, so room temperatures must be higher to equal canopy temperatures under how. As far as spectrum goes, there is still quite a bit of debate. I'll defer to people more knowledgeable than myself on that one.

Greengenes707 said:

Way too cold. Your plants metabolism is almost off if it's only 68* at lights on. And with no IR heat in the beam via LEDs, its way worse than 68 in sun or under sodium. 75* at the lowest. You'll have better results closer to 82-85*.

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Ambient is 68 in the house. Temp with lights on is currently 77-80f in flowering tent and a bit colder in veg tent but this isn't a temp problem. The severity of the symptoms is not temp considering I've grown this plant in multiple temps under different blurple lights(I added lights each grow which increased temp til replacing with cobs which I'm using to grow a different strain currently).