Got the dreaded leaf taco going on but still confused

Saw that one of my plants got the taco leaves, so disheartened she was doing so well. She's the biggest lady of the bunch actually. Ive done a little digging and found some possible causes but can't seem to pinpoint it. So from what I've read it could be Mg lockout due to ph not being in range so I first thought ok maybe ph. Checked runoff and ph was at 6.8 and ppm was at 440 which to me is acceptable but of course defer to you guys as I am definitely a newbie. Not only do I have the same strain growing right next to her without any of the taco thing present as well as one other strain that shows no deficiency or unhappiness with grow conditions. This is literally the only lady that seems to be troubled, now I'm troubled because I can't figure this out. Def need your guys help badly. To give you more info...Humidity stays pretty steady at 50% and they're in week 3 of veg from seed. I've heard it could be heat stress, but that's surprising if it is since my 600w MH is something like 3' or more above this plant/canopy which to me tells me that they are not getting all they can be from that bulb at their age and in theory I shouldve already lowered it to minimize stretch. I was actually considering lowering it right before I went in to say hello this morning and that was definitely the plan before this problem reared it's head. The reason I had it up so high was because I put em under the MH at a very young age and when I saw they could take a little more was when I was going to begin to lower each day. Only now I have this taco situation and it's throwing me off. I don't know which variable it is because nothing is glaringly obvious at this point and I don't want to wait until it gets to that point. Not tryin to be a hero here, I'm callin out for backup! I'm so confused and need help guys. Can ya help a gal out?

defintely sounds like shes "praying for magnesium" as a reuslt of pH lock out (your run off is a bit high mate for hydro or coco, but what medium are you using?).. very hard to tell without pics though... do you have very purple leaf stems?

to address your heat stress concerns... I tend start mine (600w) at 5 foot+ when bringing them in from vegging under cfl... they always bleach a little (but not curl) and after about 4 or 5 days I can start "inching" it down, this happens no matter what age they are when I introduce them (to the HPS)

I posted 4 pics up do they not show up on the post? Medium is coco

thanks for clarifying

so what range is the pH when you're feeding? and what do you use to adjust pH?

the pics aren't showing at the moment mate, maybe they need to be set to "public" in the folder?

Tacoing, I'm assuming upwards cuz the pics didn't work ,are typically caused by too Much light. Sometimes low humidity but usually light

Are the leaves folding upwards from the center vein? Or are they folding downwards from the center vein?

Vintage1969 said:

Are the leaves folding upwards from the center vein? Or are they folding downwards from the center vein?

Click to expand...

Good Q. If up its too close too the light or too hot. If downward it's too much N typically.

comments removed. I realise the OP never came back...waste of time comenting lol

Yea ok thanks, but just my 2 cents.. Leaves taco-ing down can be Broadmites too

One of my plants was stunted and doing the leaf taco upwards I though it was maybe low humidity or mag deficiency but it turned out to be the water from the tap started given em r.o. Water and they started to grow again no more curly leafs

440 ppm and got the taco goin on I'd say she hungry

Tacos have their upsides, and their downsides too.