1st WW hempy

So had some good growth this week, thinking i need to up the nute strength a touch and squeeze another watering in. First time in coco and with these cfl's it doesnt dry out very quickly but the res is drying quicker than the medium. Had a leave burn from what looks like contact with nutrient solution and something that looks like the leaves are being eaten if anyone has any ideas? Did cut off the affected leaves and think I'll do a leave strip sometime this week. Thanks for checking this out👍