Help - Wasting to many seeds - Same problem re-occuring

Hi guys, a newbie here, i keep having the same problem, i had 3 Hawain Haze babies and they all went the same way as the Northern Lights Picture i've attatched, it is about 10 days old and is grown in rockwool till sprouted then the rockwool is transplanted into coco, where i water them for the first time.

Im growing in a tent under a eco light grow bulb 125 w, 50-60 hz, 6400 k

Can anyone shed anylight on this please?

Wow...havent seen anything like that...sorry all I can tell you is...change your whole start up...dont start in cubes but on paper towels and once you see root put straight into soil. That works and you will hopefully avoid this problem...if not, its something you do.

Though I am sure you can still safe this one...good luck!

Yeah i use tap water, but i bring the ph down to about 6, i have no idea how much sodium content is in there, how would i go about finding that out?

Would using bottled water help?

This morning the problem has spread right across the leaves and the new smaller leaves dont seem to be growing they are just curling up.

When i start my last 3 seeds off do you think i can put them straight into coco after soaking them in paper towels to get the tap root showing?

If i put them straight into coco what do i do about nutriants as coco has none right?

Or do you think i should get some soil out of the garden?

Im in desperate need as i only have 3 seeds left out of 10.

basically something toxic is happening to your root system and it is not able to deliver water to the leaves. This can be:
1, Too many nutes
2, PH
3, To much water - root root

3, rockwool holds a lot of water, probably put your cubes through a salad spiner, this is for root rot, just keep your medium more dry.

2, PH - do you have aPH meter,
gotta go more later