Brown tips from bottom up

[draxcel]

Hi growers,thank you in Advance.
This has started some days ago and Is progressing from bottom leaves up.I am in Coco coir,using canna Coco and canna Coco A+B.

I have also seen brow spot in some leaves and had some calcium issues with my tap water very hard in carbonates.

I feed to runoff 3 times at day with drippers at 0.8Ec to 0.9 and having run off values of 0.3-0.2 EC.Very low.

Upper leaves though are showing nitroxen toxicity or clawing.Any help?
Those are 35 days old autos and having same issues of leaves from bottom up getting crispy and Brown.
Temps are correct 22-23° C
and Rh 65 to 60%

One plant has a strong N toxicity while the other Is only experiencing Brown spots on some fan leaves and also this Browning from tip and shriveling.


Also I am using a lot nitric acid to bring pH to 5.8 due to my hard tap water.

I inoculated mycos and thricodermas and White spores all over my pot since weeks.

 

[2budz]

I don’t grow in coco or use those nutes. But based on your pics I think your plants are doing pretty well. I see a little clawing which is probably a slight N toxicity but doesn’t look like much to worry about atm. I usually strip all the lower leaves off my plants as they get discolored. As long as it’s not moving up the plant I don’t think it’s anything to worry about.