Leaves near that are closer to the top are turning a light green. Could it be the light?

Could really use some advice here. The tops of this plant are starting to fade out to a lighter green and some of the stems have purple lines going up them. This is my first grow and I’m sorta researching and guessing at this stage of my experience and don’t wanna assume the wrong thing.

This auto is at week 6, and has been grown in Fox Farm Ocean Forrest, with a bit of dolomite and about 35% perlite.

I am feeding it the Fox Farms trio nutrient line which consists of Grow Big, Big Bloom and Tiger Bloom. It’s also given CalMag about twice a week with regular waterings.

My last feed, I gave it 2.5ml of Grow Big, 7ml of Big Bloom and 7ml of Tiger Bloom with an additional 3.5ml of CalMag. I also added 1tbsp of molasses. All mixed into 1 gallon of water. This is roughly 50% of the Fox Farm recommended dosing guide, with a bit less Grow Big at around 25% as I am trying to phase it out. The settled ph was 6.52 and sat at 713ppm.

Yesterday I started to notice the fading at the tops a bit more than the past couple days. Some leafs were showing some slight fading in between the leaf veins with developing brown spots. This seemed like it could of been a CalMag issue. Today I had to water it again and gave it 1 gallon of water ph’d to 6.61 and 4.5ml of CalMag. PPM was 303 after adding the CalMag to my water (which sits at 170ppm out of the tap).

I’m growing my plants under a QB and this light green fade is only at the tops of the plant, and most of the lower growth that isn’t directly under the light seems to not be affected. I’ve seen photos online of plants that are too close to LED’s and they exhibit this light yellow/green fade at the tops. This plant is the tallest after stretching and at its closest cola, it’s 14in under the light. Lower colas sit about 18in to 24in away. I have the light just about as high as I can put it given the other plants growing in my tent not being as tall.

Does this appear to be a nutrient deficiency, or could it be related to the light distance? I’m not sure if it could be a deficiency off the bat because of the feeding it received this past Saturday. So I’m a little confused. The lighter tops started recently, probably within the last 3-4 days. It did not seem to be an issue when the plant was further from the light.
 

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Wattzzup

Well-Known Member
In this situation I would raise your light until you get it under control. Once you get it fixed lower it back down.

also Some light details so LED guys can help with distance etc.
 

Boatguy

Well-Known Member
How hard are you running the qb? When i had a single at 140w i had to keep it 18 to 20" away. With 2 in there at 70w a piece i can get them within 4" without a problem
 
How hard are you running the qb? When i had a single at 140w i had to keep it 18 to 20" away. With 2 in there at 70w a piece i can get them within 4" without a problem
its 200w board, and it’s banging out at 200w. It has a dimmable driver, but I don’t have a dimmer hooked up.
 

Boatguy

Well-Known Member
If your temps are ok and you have good air circulation, that distance doesnt seem too bad.
May be the beginning of an overfeed situation. I always used the water, water, feed regimen when i was using liquid nutes in soil. And dosage was half of recommended when i did feed.
 
If your temps are ok and you have good air circulation, that distance doesnt seem too bad.
May be the beginning of an overfeed situation. I always used the water, water, feed regimen when i was using liquid nutes in soil. And dosage was half of recommended when i did feed.
Yeah temps are all around 79-82f and I’ve got two fans blowing now. I will take your advice on the overfeed and switch to water water feed. Currently I’m doing water feed water. My runoff ppm was higher than usual. Typically when I feed, the next time the plant gets plain water it has a way lower runoff PPM. Usually 300-400ppm. This time it was actually higher than what I fed last time. I always try to check the runoff ppm to see if it’s lower than what I watered in, or somewhere close to it +/- 150ppm. So this time I saw 800ppm+ draining out and since that was higher than the last feed ppm, it shocked me a bit.

I’m still trying to figure out these liquid nutes and this FFOF. Im just gonna back off for a couple weeks and see how things go. I did move the light up as well, so I’m gonna run this height until this weekend to see if the issues have ceased.
 
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