PH problem? pic

I'm guessing this is a PH issue, due to the fact I have never PH'd anything. Let me know what you think.

nitrogen def...maybe.. could be nute lock or underfeeding..more info plz and full plant pics...we need to know plant size age pot sizes soil being used feeding habbits what nutes u use an so on...details details details

I'm using green light super bloom 12-56-9 (i think), and hydrorush 7.5 ml per gal, and molasses at 1 tsp per gallon.

MG potting soil with MG perlite 30%.

Tap water, hard.


Should I stop using tap water?