While I'm on my first grow as well, I've spent countless hours reading through the forums, and did not go into my grow without first gaining a shitload of knowledge. So, I was a little bit surprised when I did the exact same as you, and ended up killing all of the seedlings on my first batch. I got them to about the same point that you did, and all of the sudden I wake up and they're all slumped over like they're drunk. I wasn't watering too much or too little, I was using FF soil, I wasn't using nutes yet, I had them under CFL's and my temps were under 80, and they still died. Meanwhile, I had a bagseed that I've been growing, and it's totally flourishing.
Here's what I eventually attributed it to: Those stupid peat pots that I was using. Seriously, those things are awful. The only difference between the bag seed and the dead
seeds was the pots that they were started in. The bag seed was in a little black plastic pot, the others were in those peat pots. The peat pots dried out incredibly quick, and I could never retain any moisture. So, I was having to water them too much in order to not have bone dry soil, but they were just drying up immediately. All of the moisture was evaporating out of the sides of the pots. I since switched over to plastic pots for my current round of
seeds, and I haven't had a single problem. Watering every other day, and all is well. My recommendation is to throw those peat pots out, they really should be taken off the market.
Not to say that this is why they died, but it wouldn't surprise me since your situation seems eerily similar to mine.
Best of luck!
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