New grower confused over a probably common problem

Hello everybody.

I am currently one month into my first grow and everything has been going smoothly until now. She is growing in coco coir/perlite with canna coco nutrients, and is hand watered by the "pot lift" method. I am using a Hans panel LED in a small grow box indoors.

Now my problem is that the lowest leaves are now nearly completely yellow, along with the tips being brown and seems dead:


Also the second set of leaves are starting to yellow and tips turning brown:


Other than that i think she is looking quite healthy:


By reading here and through google it seems as if there could be a lot of causes for this problem. Nutrient burn, K deficiency, and even nitrogen deficiency seems to fit here.

There are a lot of extra details in my grow journal:
https://www.rollitup.org/t/small-stealth-scrog-hans-panel-led-grow.844044/

I will be very thankful i you can shine some light on this problem!

A plant that small needs a tiny dose of nutes compared to the manufactures guide on the back of the bottle for a full strength. If you adding more than 20% you probably burning it.

Thanks a lot for your response Ninjabowler!

Does it look a lot like nute burn to you? i have been careful and am using just below the amount that this generated chart from canna is showing: (4.5ml A and 4.5ml B)

But maybe you are right and i should cut it down even more.
Again, thanks for responding!

All of the leaves that I see in your pics that are dying are leaves that are expected to die pretty early in the life cycle. I would not get too concerned unless it starts moving above that 3 point leaf.

It looks like it was nute burned as a seedling. The 2nd set of leaves look burnt. The first set could be yellowing and dying off as a normal process (as @Bugeye said). But, I don't think it's normal for this to happen so early. I wonder if it's not getting enough nutes now and sucking N from less productive leaves. That's normal, I thought it was later.

az2000 said:

It looks like it was nute burned as a seedling. The 2nd set of leaves look burnt. The first set could be yellowing and dying off as a normal process (as @Bugeye said). But, I don't think it's normal for this to happen so early. I wonder if it's not getting enough nutes now and sucking N from less productive leaves. That's normal, I thought it was later.

Click to expand...

Hey az, I went back and checked my photo journal (kinda nice to have weekly pictures documented here!) and found that I started losing my cots around week 4 and my tri-leaves didn't go away until week 7 or later. So you may be right that they are going a bit early. But I like the leaf structure on the top leaves so I still wouldn't worry too much about it.

They dont look that bad, really dark green so i figure theres definitely enough food for her it could be a drainage issue. Are you allowing enough water to pass through the coir to remove old salts? The other thing could be whats happening to the water when it runs through? Does the plant sit in the runoff and reabsorb all the salts that just ran through it? Cause if it does youll eventually get burn no matter how low you feed lol

Thanks a bunch everybody for the many responses!
Even though your responses is slightly conflicting i have chosen the "safe" route, and cut down a bit more on the nute concentration.

I always tried to get about 20% runoff after each watering, and made sure to pour it out right away so she wouldn't take a bath in the salty runoff water. Though this time i tried with extra runoff. 40% - 50% i think.

She sprouted at september 8 and I gave her the first low dosage of nutes at september 17 because i could see a lot of root growth, and thought it was time. Maybe i was to early on there and that is what is showing now.

Nevertheless, the problem hasn't gotten worse. Obviously the leaves that were already yellow hasn't magically cured themselves, but the rest of the plant still looks fine and i don't see any spreading of the problem.

Here is a couple of pics taken a minute ago:


Again thank you so much for taking out time to help out a noob grower like myself!