Newbie need help diagnosing sick plant.

Im growing in soil using vegamatrix bloom once a week at 8 ml / gal.PH is between 6-7. This is our second attempt and we are seeing the same thing happening around 4 weeks into flower. Leaves on newer growth start to turn a rust colored along the edges and in between veins. What causes this?

Your 2nd pic, I see a phosphorus issue

Thank you. What are you basing that off of?

pk def locking out Mg,mn,zn,and fe. Fix: Flush with plain water 3x amount of soil, then in the last gallon full npk nutrients at 1/2 strength. GL

Sthally. IMHO. I would say Magnesium deficiency, its common in door, the leaves and middle develop Yellow pacthes between Dark Green Veins. Rusty-Brown spots appear on the leaf margins ,tips and between the veins, and the leaf tips curl upward before dying...... Treat by watering with two teaspoons of Epsom salts(magnesium sulfate) Per gallon of water, for fast results spray the foliage with a 2 percent solution of Epsom salts, if the def. still progresses to the top of the plant it will turn green there first. In four to six days it will start moving down the plant turning lower leave progressively green. continue a regular watering Schedule with Epsom salts until the symptoms are gone or you can add fine dolomite lime to the soil.

Looks like salt buildup, especially considering the age of the plant (it's common to have buildup early in flower). I see some K def, Mg def, P def (or could be Ca def). Whenever it looks like a few things, I think lockout due to buildup.

What are the ppms of your runoff? I monitor mine when using a new soil or nutrient. If I see it rise to 2000ppm, I'm in the danger zone. I start seeing deficiencies at 2500. If i don't overfeed (or if I have lots of runoff), I can keep it around 1800ppm in mid flower.

I would feed half-strength nutrients, but mix enough for 50-100% runoff. Get a mild "flush" out of it. Then work up the nutrient strength while watching the runoff ppms.