[HELP] Unsure of exact issue, help diagnose

So, im not sure on the diagnosis, so I would like some help. I thoight at first light burn so I moved it further from my LED, but it appears to still have the same issue after another day. I havent fed any nutrients since planted in mid-March in FFOS so I wanted to check before I water and feed this time around.

Edit: pH for water was always around 6.5, 80 degrees temp, 60-70% humidity, FFOS soil, no nutrients given yet, watered 4 days ago, about a month and a half old

Looks like a potassium deficiency.

Organic soil starts to become exhausted around 6 weeks. Probably time to start feeding.

Renfro said:

Looks like a potassium deficiency.

Organic soil starts to become exhausted around 6 weeks. Probably time to start feeding.

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Alright thanks... Should i start at 1/4 strength or 1/2 you think?

Whenever you flush, start or need nutrients, best rule of thumb is to quarter strength and build up. Let your plants slip into those nutrients. Not jam into them

just how tall is that plant? shouldn't it be bigger?
ffof is intended for plants that are older, well established. you shouldn't put very small plants or seedlings in it because the fert load is too much for small plants. You have dark green leaves with dying tips which usually means over fert. at this point, since it's already planted in that soil, I would just water when dry and don't bother pHing the water down. chances are the soil is down low enough as it is. I don't know where people get the idea that your water always has to be pH'ed below 7. Not true.

It's about 2 months old. I already watered and feed them, I was at 1/4, but I did test the runoff at near 5.0 pH. So for reference no more feeding that plant until... It gets healthy then starts to show discoloration from being hungry?

That looks like three plants put in same pot; is that what that is? Let it get at least one foot tall, maybe two, then transplant into much larger container, like 20 gallon tub with ffof. then just water. don't test anything, don't pH anything, and don't feed anything... and see what happens. come back here if you suspect a problem.

Those plants will fight for root space an exhaust that medium even faster. No reason to put multiple plants in same pot .
Now each has 1/3 of room and available Nutes ... hence your deficiency. And adding stressors to grow that will stymy normal free growth.

No feed will correct the limitations you put on those plants b

asylumhavoc said:

It's about 2 months old. I already watered and feed them, I was at 1/4, but I did test the runoff at near 5.0 pH. So for reference no more feeding that plant until... It gets healthy then starts to show discoloration from being hungry?

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Those things look like they're super close to the soil, almost even touching it. That might be part of your issue.

F2f is hot...You may not need any fertilizer anytime soon. Good to know it survived this far...I see a lot of young plants in Ff that look pretty bad. Kind dark green. It'll probably be ok. Not sure if I'm buying the P def idea. FF will list the analysis right on the package. It shouldn't be lacking anything.
Thinking mb it's a micronute. If anything that may be it. Most good fertilizers have a full complement of micronute so that may be the ticket.

Well, after feeding them the nutrients and getting my new lights in, the new growth is looking better. I topped them its one plant per pot. They have both been topped 3 times for 8 mains, with the largest one getting another top for 16 (using them for clones). I haven't watered yet since the medium is still a little heavy and I want it to dry out a good bet to help the roots before I water again. I'm going to strip the lower growth off soon as I water as well and they look like they can take the stress (cloning included). Everything else is just going to be LST from here.