My plants appear to have a nitrogen deficiency. I fert once a week with medium mix of 2-1-1 earth juice grow. Am i underfertilizing them?

With two batches they look green and great til late vegging (3 feet) when all leaves begin to turn yellow curl upwards and die! This is sad
PH is 7.2

Any help?

Im new at this bro, what i did was mixed 1/4 of fox farms grow big, 1/4 cal mag and 1/4 super thrive as my feeding gallon. and a seperate gallon with just ph'd water and 1/4 superthrive. i keep my ph at 6-.5-7.0 usually 6.8 and i water 2 times and feed on every 3rd. watch the lil guys and they will tell you, i plan on uping my nutes to everyother and half strength in a week. So if i where you i would get that ph lower, and go get a nute that has a more balanced NPK ratio.

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I do not condone drugs in the USA. All Photos I post are photos from Google Images. Everything I say is fictional Because I have nothing else better to doMY 1st closet grow GOT GWAP?