leaves curling up into a tube shape need help

Hello everyone,

I am in need of some urgent help, I have several plants that a few of the top leaves became shiny and the leaves started to curl up from the sides, the leaves now look like tubes as the sides have curled to the point of touching the other side, the leaves are still rigid and firm. the strain I have is Masterxbubba kush, I have had several successful grows with this all from cuttings, recently I have changed several things, listed below

I am now growing in Coco., used to be Aero/nft in tubes
I am now using advanced nutrients Sensi grow, used to use dutch master gold
and will be going back to it after i run out.
I am using a 400w sunleaves bulb with a digital ballast and 5ft light rail, recently I moved the clones from 250watts of T5 flouro.
I have also started using mycrogrow from fungi perfecti.

The room is an articificial environment at a room temp of 80 and an average Co2 of 800ppm humidity ranges between 40-60%

one last note, I did see this problem with some of my earlier mother plants That I had in a recirulating DWC setup When I added the sunleaves bulb to it, at the same time I over nuted the mothers (due to my ppm meter calibration being off), as soon as I saw problems from the mother I took the healthier branches and made new mothers the clones I am growing are from these mothers.

I have also had some problems with the PH, Earlier I thought that the range in coco should be the same as in soil, but know better now and have readjusted back to 5.5-5.8.

Any help would be beneficial as everyday I am seeing more and more of the same symptoms.

Thank you

what do your stems look like ? purple? streaks orsolid color?

The stems are firm and look healthy, The coloration on the stems near the base is 95% green with purple streaks going vertical, these streaks become more predominant closer to the top, wher it is still streaky but around 80% purple.

yesterday I did a watering with only H2O, with only a couple of cups of water not enough to completly flush the coco, as the coco was not yet dry enough for a new watering ( did not want to risk other problems)

One other thing I forgot to mention is that my media is 75% canna coco,20% perlite and 5% higromite, the higromite is in a layer in the middle, I don't think that this would be the problem but at this point I am at a loss.

Oh by the way this is only happening to the top 2-3 leaves, but I am having lots of lower internodal growth, that looks to be on the lighter green side.

so here is a couple of photos, anyone know whats going on?