also take care not to leave moisture on leaves when under light as they will fry, inside or out water on the actual plant will cause a few problems, but this baby isnt suffering from sun or light burn, it looks like nute burn, I wonder what the medium is and if its got nutes in it already? a seed raising mix is preferable for germinating, with some blood n bone added lightly just to fortify the soil to give babies a little extra popping power, we dont usualy feed for the first week or so and use a buffer between the new seedling and the built soil we use when u transplant, Cannabis is pretty forgiving and this may recover if u are careful, spray around the stem at soil level using a soft spray nozzle till they are a little hardier. taking care not to leave the foliage of the plant wet.