Follow me not knowing what I'm doing (Lowryder Dwarf Mix) N00B-Grow

My first grow ever is about 17 days in right now, and out of 7 seeds only two look "alright" but they kinda look like they normally would day 11 (I am guessing).
One dried and I don't know what's going on with the others.
I haven't given up hope just yet even tough one seedling tuned yellow and they just seem stunned.
I later realized that I have given them to little water which resulted in me overcompensating (idiot)
Grow-room had been too warm and dry about 86-89 F, PH lvls have prolly been a bit dodge as well.

My grow-room is a walk-in-closet which has no ventilation other than the fact that the door is open. I have yet to have a carbon-filter and exhaust-fan installed but will have that sorted in about a month

At-least I know some of my mistakes and I learn as I go.

Anyways, thought I might post my second try here, and feel free to comment on my mistakes and share some knowledge.

This is what I am going with this time:
Joint Doctor - Dwarf Mix 10 Regular seeds (Hopefully) The package says 'Lowryder mix automatic')



I have mixed about 50-50 each of the following soil-types:

Seeding Compost:

Peat H5-7
H2-8
Sand
Limestone
Mineral

PH 5.5-6.5
________

Mediterranean Soil:

Peat H2-4
H6-8
Bark Mull(? no idea what this is)
Crushed Granite
Clay
Limestone

PH 5.0-6.0

_______

About 5,5 pounds total with 2-2,5 tablespoons of baking soda.

I will add perlite later when I transfer to 2 gallon pots

I have put the seeds on germination between a couple of sheets wet toilet-paper which I folded a plastic bag around and put in a pillowcase on the radiator.
I Think I will give them 48 hours to pop.



I wont put the in the grow-room until 10-14 days have passed.

Any help along the way would be appreciated.
I had trouble with some seeds from my previous grow that stoped developing and left the seed-scales on like little helmet.

I Didn't have to wait as long as I thought for the seeds to crack, so I decided to put them in my soil-mix today.
I placed the pots in a dark cabinet this time.
Apparently this is good for them but I don't know why, I have to read some more tutorials.


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This is a photo of my first try with Diesel Ryders.
Two made it this far then I killed em...or at-least made them lose their will to live.
Luckily I only have that effect on plants.

I prepared my grow-room and placed the pots with seeds under the 250W HPS lamp.
The timer will start the lamp and the fan tomorrow morning at 06.00. (18-6)




I placed some plates with water to keep the air more humid than previously.

Room temperature is between 71,5 - 75 F without anything on.

Last time when I had the stuff running it was around 80F.
Hoping I can keep the temperatures down a bit more this time.

Advice and guidance is welcome.

This is what we got so far.
Bottom right one is a 'diesel ryder' that is quite a bit handicapped from heat (I think).
The other pots with nothing visible in them yet are apple and Lemon-seeds.

I wonder at what week, I should transplant them to 2 gallon pots?