I have better luck allowing the soil to dry out between waterings. If there is always moisture the roots have no reason to spread further looking for moisture. There will be a small ball of roots at the top of the soil. By allowing the soil to dry out, it forces the roots to expand and go deep in search of moisture. Bigger stalks and leaves need a larger, stronger root system for support. Looking at your last photo reminds me of last year when we were getting alot of rain, the soil was saturated and the pool had 2" if water as a reservoir. My leaves looked like yours. I kept pumping the water out of the reservoir and they recovered. The same happens when my tiny seedlings are in the 1020 cells. If I keep the soil moist, I end up with a small root ball at the top of the soil. If I let them completely dry out between waterings, the roots expand searching for moisture and fill the cells at transplant time and the seedlings are larger, the roots hang out the drain hole, and easier to transplant.