Bad ph + Nitrogen toxicity please help

Hello , some tips of my leaves are starting to point down and dark leaves too and on my weakest plant some canoing . I read something about it and discarded the overwatering problem , so it must be N toxicity . My feed schedule is from biobizz nutrients and i use 50% of what is recommended and started only using bio grow , acti-vera and bio heaven on 3rd week . It is now day 6 of week 4 in vegetation and i only feed once a week with 50% of table recommended nutrients , that means 2 feeds .

Today im watering with plain water , the problem is that i used a buffer today and found out that my ph reader was off by 1.0 + ph point . So instead of watering with 5.9~6.0 i have been watering with 4.9~5.0 ph .

Could this be the cause of Nitrogen toxicity or some problem with biobizz feeding , btw i use all mix soil and genetics are og kush from dinafem.

I need to water today and im unsure to what ph should i use , adjust to help with this situation and to what for , or should i apply 5.9~6.0 ?

from this chart i should have nitrogen deficiency and not toxicity because ive been watering with 5.0 ph , help!

If you're in soil, your pH should be closer to 6.5. I wouldn't do anything but correct your pH and move forward. Once you're sure you've been feeding the correct pH and the plant has settled (in a week or so), then worry about what deficiencies you have and make the corrections. Good luck.

I learned that 5.0 ph can make the plant suffer from heavy metals like iron and aluminum change and can become toxic to your plants . MAybe this is not an N toxicity but iron or aluminium has the same effect on the plant as N toxicity ?

Anyway ive learned that i should water my plants in soil in vegetation between 5.8 and 6.1 and in flowering between 6.2 and 6.5 is this wrong ?

How does your plant look now? Did you fix the problem was it n tox or just a ph problem ?

Assuming you are in soil.
-Flush the medium with Ph'd water until you get about a gallon of run off
This should remove the salts.
- Try a compost tea to add beneficial micros to break up the salts

Assuming you are in hydro.
- Resevoir change, 50% of nutrients given last feeding, and I prefer Ph 6.2-6.3, should increase availability to absorb the remaining salts.

Hope this helps.

Happy growing!

the problem got solved by adjusting the ph , im still using biobizz full dose per week and no new burnings