Some fan leeves yellowing under the canopy!

I have some of the original fan leaves yellowing on my Jack Herrer. To set the stage. They are vegging under a 600hps(89,000lumens). I know it's not a halide but they are $120 and the hps came with it. I grew the Jack from a seedling and she is now 72 days old. I am doing a scrog and put the screen on her almost 3 weeks ago. Ther are 2 other plants in ther with her. An Orange Crush(Sativa) seedling that is 62 days old and is growing a little slow. There is also a Strawberry Cough Start that looks absolutely wonderful. Some of the biggest fan leaves I have ever seen.

So, I have this Jackand some of the lower fan leaves have yellowed. I wonder if it is from lack of light due to the canopy? The soil is 10-5-10, and I am using Sensi Grow. It doesn't look like lack of Nitro.

That is the whole plant. About 2' across. That screen is about a foot above the pot. None of the other plant are experiencing this. I just watered yesterday.

So the O.C. is the plant in the front right corner. The strawberry in the far back right, the tall one. that screen is 3'x3'
The O.C. Looks healthy at 62 days old. She is abot 18" tallThe Strawberry.

Looks like a Mg def to me. Try spraying them with a tsp of Epsom Salt per 1.5lts or feeding with 1tps per gallon

Molasses is great for micro nutrients and feeding soil and seaweed extract has micros too.

It's not the whole plant, though. Only like 5 fan leaves and they are all under the canopy. In other words the upper level of leaves isn't letting any light through. My question is, can leaves turn yellow like that from lack of light. Maybe I did water to much.

I wonder why none of the other plants have this problem, too.

pretty sure its the normal life cycle of a plant, everything else looks good but im no expert.

Yes, you have answered ur own question. Remove them as they are dying and if any leaves are 50% damaged you can remove those too.

At the end of the flowering cycle u can expect the whole plant to use of excess N and go yellow.

They are still vegging. I went and cleared out the lower levels that just didn't look healthy or weren't going to ever reach light. I also did some fimming I think it is called. I trimmed off some of the starts. I will also wait an extra day to water, which will be tomorrow. All those plant are barely 2 months old. I think I will Vegg them for another 3-4 weeks. We will see how fast they grow.

This is my flower

Perma frost and Ceaser Skunk

Your flowering plants look great. As long as you keep up the nutes then they should be fine.

Great work !