Unfortunately there's a bit of art to dialing in nutrient levels in soil. I would just keep flushing those plants with pure water until the leaves straighten out and they start looking a little hungry for nutrients. I made the mistake when I first started in soil of using a rich soil plus a lot of nutrient, which just burned the crap out of the plants. Start low and just add slightly more until the very tips of the leaves start to burn and alternate pure water & nutrients every other day.