Help me diagnose my lemon skunk issue please +rep

Lemon Haze 1 month old in veg
400w hps
gardenscape potting mix
feeding ff grow big every other watering half strengh
PH 6.7
Temp 73 f
humidity 47%
cooled hood no heat radiating from it light kept 10 inches away.

I am trying to determine if this is some type of lockout of nute burn. I am guessing its a build up of nutes.... I flushed, runoff was 6.5 and I re fed with a quarter strengh about 30 min ago. I would just like to figure this out so it doesnt happen again.

I have 5 different strains going and this is the only one showing these issues....maybe genetic?

anyone????

Maybe Mag deficiency, but I'm not completely sure. Are you using anything to supplement magnesium intake like Cal/Mag ? If not, consider adding 1/4 tsp of epsom salts (magnesium sulfate) to every gallon of water you use. Even if it's not the problem this time, it could help prevent it in the future.

Good luck man. I hope this helps.

Looks like Mg deficiency because of the interveinal chlorosis. Is this starting on the lower leaves?

edit: I misread your post. Your nutrient schedule seems fine. How often are you watering?

I am watering as needed, I let the soil dry out right now it seems to be every 4-6 days. It actually started at about the same time on all of the leaves working its way from the tips inward