...what are you growing in TRED? What brand? ..How are you testing in-pot pH? I ask because it's a bit early for such defc. to start, especially if you have fed them anything, so soil/soilless media pH is a more likely cause for these symptoms... Are symptoms still progressing? This type damage will not repair, you're looking for a halting of progression... Another possibility is that splash burn from droplets and light, the deformation can be aseparate issue, not uncommon in young leaves as tissues expand,.. any scarring/damage can make this grow out unevenly,..