Yellowing leaves curling down. Any ideas?

Seedling is Dinafem White Cheese Auto.
Growing under 3 40 watt 5800k cool white cfls and 2 23watt 2700k cfls in cabinet lined with Mylar.
Started seed in MG Organic Soil after germination but realized it may be a bit hot then transplanted into a lighter soil (Earth Gro) 60/40 mixed with perlite. had no list of nutes in it so figured there was some but not as much about 12 days in.
Temp is 70-80 with lights on with one small fan circulating. Soil PH is 7.0. Humidity 35-50%
Plant seemed to start off ok then just after week one lower leaves began to yellow with brown spots and curl down. I assumed over watering as I was giving it about a 1/4-1/2 gallon of bottled water every 3 days NO NUTES, but soil has seemed to be dry each time, most likely me being a over watchful newbie.. Growth has slowed big time...and now top leaves are doing the same.
Any feedback or advice on how to approach this problem next will be appreciated! Pic to follow

Some pics posted. Any ideas?

could be: too much water or temperature of water ---> roots are starting to suffocate

do you have a digital temperature gauge ?

measure your soil temp and water temp before watering. try to match the water to the soil. if soil is cold than try to warm it up to 20 ish to 24C.

Hibok, thanks for the input! I think you msg be correct about the soil temperature. Took the soil temp just after the lights came back on.. Only 17C and the water the same. This won't be a difficult adjustment to make, just hope it bounces back well. Does it look like it has a shot?

yes , give it like 3 to 5 days to recover and from there keep the temps steady and constant.

Thanks again! Hope this does it it and I really think it may, my grow room was flawed as the pot was on cold ground and temp is hard to maintain but now the whole set up is enclosed so we will see!

yellowing and curling down of the leaves may be an indication of some pH issues. check on the pH of the soil. they might be unhappy with soil pH