Help to diagnose leaf yellow/ dying problem

Having a little issue with a couple plants which I hope I can get some help with. These leaves are usually at the bottom and working up now to the middle.
The nutrients are flora grow series with cal-mag. Right now I am at 7 weeks veg and about to move over to flower but would like to fix this issue first.
Ph level is 6.1-6.2.
T5 fluorescent lights
carbon exhaust system with fans and fresh air.
No ac.
Temps sit around 75-85 with humidity 35-55

I am thinking either a Nitrogen deficiency or Magnesium deficiency.

Any help would be appreciated.

Your were correct Nitrogen deficiency

Solution to fixing a Nitrogen deficiency

Avoid excessive ammonium nitrogen, which can interfere with other nutrients. Too much N delays flowering. Plants should be allowed to become N-deficient late in flowering for best flavor.
A goof solid N-P-K ratio will fix any nitrogen deficiency. Any chemical or organic fertilizers that have Nitrogen in them will fix a nitrogen deficiency., Peters all purpose plant food 20-20-20 is good, Miracle grow All purpose plant food, Miracle grow Tomato plant food, (Only mixing at ½ strength when using chemical nutrients, or it will cause nutrient burn!) as well and blood meal! If you need to give your plants a quick solution to nitrogen and you want to use blood meal, I suggest making it into a tea for faster use, where blood meal is slow acting, but when made into a tea it works quicker! Other sources of nitrogen are dried blood, Cotton seed meal which is slow acting, Insect eating bat guano which is fast acting. Bone meal which is a gradual absorption when not made into a tea.( also excellent source of phosphorus). Fish Meal Or Fish Emulsion is a good source of nitrogen and is medium acting. Worm castings, which is gradual absorption. Seabird guano, All purpose Millennia Seabird guano, Orginal Seabird guano All Purpose, Crabshell ,which is slow absorption. Fox Farm Grow Big, which is fast acting. ( can bring down your ph
If you need my more info on this I have J st ask.



+thanks/like to @garrigan62, the level of help I continuously seeis what keeps me here and ONLY here. Now back to the regularly scheduled subject, :stuck_out_tongue_closed_eyes:
I had the same nutrient deficiency, luckily for me it happened deep into flowering, I backtracked and realized that I switched to flowering nutes the same day I switched my light cycle, I wont do that again

When switching over…go slow. Ween her off nitrogen. You’ll have muchetter results.


Thanks, much appreciated. Hopefully will see some change with this nitrogen booster.

Hey Garrigan, I was wondering when my plant had this look it was the ph? I know Acehole said the ph was 6.1-6.2, but I was wondering if that was the reading that he was watering with or is that the reading that was coming out the bottom of the pot? Can you please help me to understand how one can tell for sure? Thank you in advance, Mike

Hay @Acehole is that the white whidow strain from here?


@mcicchino, the water I Feed her is 6.1. The run off water last I checked was 6.2.

@peachfuzz, it is a white widow but not from here. Great strain.