Seedlings wilting and going yellow

This is my second grow and i am having major issues already. My seedlings are maybe 2 weeks old and they are going yellow and wilting.

It can't be under watering as the top 1 or 2 cm are damp/moist, and it cant be over watering because i learned about that in my 1st grow and know how to avoid it, i even let the soil dry out for 4/5 days. so i don't know what is causing the wilting.
The yellowing is so confusing, the cotyledons should be providing all of the nutrients at this stage, so maybe it is nutrient burn? i am using sterilised topsoil which i know is nutrient rich but wouldn't think it can cause major issues like this. the white stuff is perlite by the way, that shouldn't be causing the problems.

they're on a 20/4 light cycle, runoff pH was around 6.8, temp in cupboard is pretty warm, maybe 28/30 Celsius, but the strain is Big Bud, which apparently needs a warm climate, i even left the doors open for a few days and that didn't make a difference either.

Please help, both of my seedlings are dying and i just can't loose them, i'm still trying to cover my losses from my 1st grow.

It looks like its stretching a little bit.. What kind of lights are your using?

How much are you water at a time and how often?

I water it when the top 1 or 2cm are dry, its usually every 3/4 days i water it with maybe 100ml water, no nutes.

lights are like 3inches away from the leaves, they are 23W energy saving (125W equivalent) at 1380lumens Cool White 4200K

stop the watering in a pot like that u water once a week if that

mr.maryj said:

stop the watering in a pot like that u water once a week if that

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every other day , but when its a seedling like that, back off watering every day.

closer pictures and please rotate them before posting.

over watered

i dont know if its over watering. the only reason i say that is because when they started to wilt i re-potted them into a larger pot and the soil was bone dry all the way through. a few days ago i tried flushing them, but that hasnt worked.

If it was overwatering/under watering that would explain the wilting. however that wouldnt explain the yellowing, and the yellowing occured before the wilting.

yellowing has got to mean something to do with nutes/soil rite?