Problems with seedling - acting really wierd

Hi everyone, first grow here.
So I germinated my seeds (unkown strain prolly sativa) exactly a week ago and planted them in my soil (Biobizz light mix). they all sprouted pretty quickly, after about 2 days or so but now it seems like it has stopped growing for some reason.
In addition to the stunt growth the old leaves (cotyledons) and the stem seems to be getting a dark green/purplish color and the new leaves are pale green.

I am growing with 250W hps + 25W florucent to help at the begining. watering with purified water @ 6-6.5 PH. Temps are fine about 74. Fan is on them constantly while the light is on.

What is wrong with my seedling? Is this normal growth for 1 week from seed? help !

propably the hps light is roasting the pots , close the hps , get another cfl and run only them for about a week or more , when they grow a bit transplant them into real pots and light up the mini sun

You mean the hps is heating the root system too much?
maybe I can just move it away then?
on what size should they be when I transplant them?

i think it looks ok, just make sure you dont get impatient and smack it round the head with nutes. the other two are right also, doesn't need to be under hps until about the 3 or 4th node at least.

i had this problem mate, stick them in a propagator and mist the leave for a week or so and when theres some decent roots ur ready to go

So I added a 45W CFL and turned the HPS off for now. So now I have 2 CFL's 45W + 32W.
Seedlings still seem kind of wierd although really slow growth has started to occur.
I added some pictrues to explain the situation. you can see the color of the main leaves is yellowish, and the old one's + the stem are purplish. You can also see that on some seedlings the growth of the new set of leaves is uneven (is this normal?)

My question is. If my seedlings had suffred a heat stress (which I believe is what happned) is this normal then? When will the seedling recover from the stress and start growing more rapidly?

Last question - today I accidently watered my seedlings with slightly acidic water (5.5 - 6) could this cause a stress as well?

Thank you very much for helping !

help please?

should be fine - make sure it's not too cold too!
CC