Hey there!! Fought some overwatering issues a few weeks ago, everything seems to be bouncing back okay. But now I've noticed this happening to the sides of a few leaves, wondering what is going on? Temps are nominal about 75-77, humidity is around 40-50% goes up a bit more after waterings. I have a small circulation fan going, a 4 bulb t5 that I had about 6 inches above, raised to about a foot because they didn't seem to like how close it was. Seeing what happens there. I've but them in a half and half mix of promix with micos, and Gaia green living soil blend. Watering once the soil dries out, not too dry but dry enough. Is this overfeeding due to the living soil? Heat stress? The sides of a couple leaves looked like they were curling up but that as since going away...trying to narrow down every possibility. Please help! Thanks in advance. I've posted the ingredients list of the Gaia green soil, other than those two leaves (one on each) developing that brown, dying look on the side of them, I don't know what else it could be? Anything that they need that I'm not giving them? Should I raise the light for till they adjust to it properly? Any info is appreciated. Thanks!
Looks like you have a bit of heat stress going on and as the damage is limited to just a couple leaves I wouldn't worry about it too much.
6" is about where I keep my T-12s above young seedlings but try to keep them an inch or two once they are as big as yours so I doubt that's the problem. I run my 400w HIDs at 8" to a foot but have a small fan blowing between the canopy and the light(s).
Do you spray anything on your plants? That damage looks a lot like it's from moisture which can brown out leaves easy enough. Just one leaf draped over another can trap moisture in between and the lower leaf will turn all brown in just a day. Leaves breathe through their undersides so it's the lower leaf that takes the hit.
@InTheValley As you initiate flowering the plants go into overdrive and many strains start growing weirdly shaped leaves and even single-bladed ones that will be all you see as it grows from there. I don't see any signs of deficiencies nor nute burn on a couple of the older, normal looking fan leaves in your pics.
The leaves are very dark green which can be normal for some strains but usually indicates that you are feeding close to the edge of too much. If they have had lots of P and K already I'd skip a feeding and see how it goes. First sign of low nutes is the oldest, lower leaves starting to yellow. Low N a general fading of the whole leaf surface, Low Mg, the edges and between the veins yellow first. Both of those are mobile nutrients and will be stolen by the rapidly growing tops really quick.
If your pH is way out of whack you'll see deficiencies in the newer growth first as micronutrients get locked out. Here's a handy reference chart for sussing out what's going on.
Good luck to the both of ya!