Multi strain in coco feeding canna nutes under gavita hps

I left my brother to mist the seedlings whilst i was in amsterdam for 4 days, got back expecting growth but found the plants have stretched and looked leggy and not much growth apart from stretch…(should have took photos before repot) I planted the seedlings in clear plastic cups with holes punched into the bottom, the medium was very moist and wasn’t seeming to dry out soo i decided i would repot in red cups as i heard clear cups are bad for roots…(feed the girls very lighly was due to bad drainage more then over watering)… I used fresh coco and pulled away as much moist coco as possible without disturbing roots, i added great white to the medium and root balls of the seedlings and repotted burying the stretched stem as much as possible… I didn't water the coco prior or after the repot as i didn’t want to stress the plant further if the roots have been getting drowned by excess water in the coco due to poor drainage, i sprayed mist above all seedlings when all was transplanted very very lightly with a micro dose of rhizotonic by canna… 1 blueberry muffin seedling looks like its going to die the other 2 are okay. I have attached photos after transplant should have photographed before transplant but didn’t 😅 When should i water next seedlings are hard work i usually runs clones that come of a defent size and root structure…🤷‍♂️ My ppm is 150 tds from the tap Ec is 0.4 out the tap Im dechlorising my water with tap safe for 24 hours before use. I have been recommended to ph to 5.8 is this correct ? My temps are around 23-28 degrees And humidity around 55% - 80% Love for reading this far, i will be posting a update every week, Any help or advise would be greatly appreciated 👊❤️