Help with yellowing seedlings?

[Phaedrus420]

I have about 10 seedlings right now, a week and a half old. A couple days ago they started to turn light green/yellow in the center, and I may be paranoid, but I'm pretty sure it's spreading to the second pair of leaves on many of them. The veins seem to be turning yellow first, and then, the leaf starts to develop that lime hue. The middle is always the lightest, or most yellow, and it spreads out from there. I dont think it's the strain, because I have another seedling of the same that's a darker green all over. A nitrogen def would be spreading from the outside in, and wouldn't be originating from the newest leaves. My soil is pretty good for now, but I've added a diluted nutrient solution. N-P-K is 12-10-5. Too much maybe? Growth isnt stunted at all, they actually seem hardy, this discoloration aside.

............help?

[Rusty Trichome]

I have about 10 seedlings right now, a week and a half old. My soil is pretty good for now, but I've added a diluted nutrient solution. N-P-K is 12-10-5. Too much maybe? Growth isnt stunted at all, they actually seem hardy, this discoloration aside.

............help?
What soil are you using?
What lights and schedule are you using?
What's your water ph?

Your seedlings are too young for adding nutrients.