Yellowing on top leaves in veg....

Hi there! First grow, hempy style. I've got one plant 3 weeks ahead of the others and i'm worried about some yellowing on new leaves. The new ones I've started use perlite/vermiculite mix so i tihnk they will retain water better but the old one is 100% perlite....I'm thinking maybe it's thirsty since it doesn't have the verm to hold water in?

I'm watering every 2 days and feeding every third watering....so a given week is like this

day 1 - water
day 2 - nothing, mist tops
day 3 - water
day 4 - nothing, mist tops
day 5 - feed full strength
day 6 - nothing
repeat....


Is that perhaps not enough for the plant in 100% perlite?

The strain is a bagseed afgani indica.

Temps are a little warm in the low 80s, but I've read that ok. Air circulation is ok. Water/Nute ph is fine, feed is gh nutes lucas formula.

Thanks!

EDIT 1: I should note that all of these (the seedlings as well) drink their water in a day. Every morning the res in the bucket is totally gone, so on those days inbetween waterings it's basically got nothing. I was under the impression that wasn't such a bad thing since it would strengthen roots.

I guess my question now is should I be watering every day or every other?

Here's pics....

Damage seems to be uniform over nodes....pairs of leaves seem to have the same discoloration. Black spots have appeared on some as well.

Appears to be getting worse and now some of the newer plants are showing symptoms as well. I've narrowed it down to either fluctuation in PH or high temps (high 80s). Some further insight is appreciated!

They are losing their chlorophyll...pH NEEDS to be checked ASAP. If pH is fine...it is in dire need of some nitrogen.

It appears my problem isn't going away....I've increased nitrogen by double (really should be plenty) and I'm always careful my PH is around 6. What gives? Any other possible diagnosis?

It does seem that unlike a nitrogen def, the whole leaf isn't turning straight yellow uniformly...the yellow works it's way in the the outer edges of the leaves.

Another symptom is purple-tinted stems for side growth. On some plants the main stalk has purple streaks through it too (dunno if it's relevant)

This scourge favors big fan leaves and low fan leaves.

See Below....

• pH ~6ish every feed
• RO water so nothing else in it
• Temps low to mid 80s, high 70s at night
• 400w MH, not too close, not too hot, plenty of airflow
• Not overfeeding
• Using reverse lucas formula (10 micro 5 bloom since I'm in veg)

If it makes a difference, these plants have been vegging for a month and a half but are small due to being rootbound in 12oz cups for too long. The strain is bagseed but supposedly is some kind of pure indica afghani.


Anyone got any idea what I can do here?