Curling leafs, need help.

Above is 2 pictures of my plants. They are roughly 3 weeks old, and the water leafs have already died off and now the next set of lower leafs are curling over. I have them in merical grow potting soil. I feed them every 3 days with merical grow organic choice ( chem props are 5.4% other water soluble nitrogen, and 2.6% ammoniacal nitrogen) It don't mention phosphorous or potash and the numbers are 8-0-0. So is it that I am not feeding them enough? Or I need a concentrate with potash and phosphorous?
I was told this plant food would work on marijuana, but it seems otherwise. My leafs keep dying =/
If you could please help me out I would greatly appreciate it. And if you know of a better (obtainable at walmart, lowes, home depo ect.) plant food, please tell me where to buy it.
Thank you.

And I mist the plants every like 2 days. And I go on and off with water and plant food. Water every 3 days, then food, then water, ect.

Try snipping off those worst curled leaf, and look at the bottom of the leaf with a microscope. Check for spider-mite eggs, this is a possibility.

I use foxfarm nutrients and though I grow hydro this has happened to me on early plant stage.you could be giving them too much nutes when you feed them.If you can stay away from miracle grow you can use it but your plants may have issue go to a garden store and they will have better nutes for you.Dont start your seedlings or baby plants with a full dose of nutes cut the dose at least by half.

if your new like me, you are probubly watering them too much with too strong of nutes. My plants looked exactly the same. I was using 1/2 strength 3 part Gen Hydro nutes from the label on seedlings and that is what they looked like. Then chopped my measurements in half from that for another week and they looked allot better. M-Grow sucks, try better nutes from any gardening store. Chill

miracle grow , does that have those little yellow fert balls in the soil ? for starters every 3 days watering seams to much to me , how big are those pots ? try 4-5 days every water , plus if the soil does have those little yellow balls then theres your problem by u watering every 3days your releasing nutes and most likely burning up the plant.