Yellow leaves

This is my first grow op. Its been almost 3 weeks for a few of the plants. My biggest plant is turning yellow and dry. Can anybody tell me what the problem is? Thanks

you giving it nutrients already? It looks overwatered a little and nutrient burnt...how often are you watering them and what are you feeding them at this point?

I have some of those same pots...i find the holes in the bottom are not large enough to drain well...i took the base right off mine to compensate.

I water them maybe every once in 2 days. I started mixing in Fox Farm Big Bloom with the water last week just for the bigger plants. Another thing I wanted to ask was when do you think I should move them to like 3 galllon pots?

i have this problem too look at the leaf 1 week into flowering.. its only affecting bottom leafs..

Should I move my bigger ones into gallon pots?