Yellow large fan leaves

[Beeman]

So I got up this morning and saw this, yellow leaves seem to be the large lower fan leaves are yellowing. Her is what I have going on.

Grown in 3 gallon bags in fox farm happy frog, using gh floral nova series(bloom) at half strength. Been adding Calmag 1teaspoon per gallon, grown on auto pots. pH going in 6.25 ish temp at night in low-check it everyday it goes up to about7.2 in the next day. I adjust it daily to try to keep it between 6-7. Tent is 4x4x8 vivosun 420 watt led light about 16-18 in above plants temps at night lower to mid 70 during day with light on 82-84. Did get a few hot day it got into the upper 80s. What am I missing here.? Think the pH fluctuations is causing the yellow? Do have a few yellow flecks in some leaves too.. I noticed I have some painted nails on the tips think the nutes are still too high.i have been lax on ppm tracking. Couple times I did check were running about 1200-1300 too high? Any advise

[MiguelEnfermo]

Is that Fox Farm Happy Frog a Coco blend? If so, I keep my coco pH a little lower, like around 5.75 and full strength nutes at this flowering stage. To me, they look hungry and the pH might be locking out nute absorption. If it were me, I would flush with 5.75 pH water and make a fresh batch of full strength bloom nutes and apply. My two cents.

[Beeman]

Hey Miguel, these plants are in straight happy frog soil didn’t add any coco blend I did add some perlite. But I think you right on the pH it keeps drifting up so I’m think maybe flush at a high 5 or close to 6 pH and try and get and keep the pH lower. I see you have seeds from freeworld genetics. Have you grown any out? This current grow is from them .The Suplex, Peach breath and had a leftover from them from my very1st grow back in 22-23 Jackie freeborn. I like their beans and pricing on them is pretty good. They had some sales on them this past winter and loaded up on some. Thanks for the reply and advice.

[Orggrwr]

I believe interveinal yellowing on the lower leaves is a mag deficiency. Might want to hit them with some Epsom salt next watering. It works well as a foliar spray also.

[Radeon]

She's pulling nitro from the lower fans because she's getting ready to finish. If you zoom in you can see a couple pistils starting to change (not on a top). Just a couple, but enough to tell you anything you add now is gonna end up in your bud. Let it go, won't be long. They gonna swell up now. Good job!

https://www.growweedeasy.com/yellow-leaves-flowering-marijuana