the second pic shows some droopage which is in most cases over watering like you said. You can start by letting the clay pebbles get near dry before watering at all again. Also, it looks like you have plants at different stages of life or the pictures were taken at separate times not sure. Anyhow, back off the foliar feeding a little bit and also back off the water and you should be fine. It also wouldn't hurt to back your pH off to about 5.5 or 5.6 for now also. 6.2 is just a tad on the high side, although at seedling and clone stages they require more nitrogen, which can be effectively absorbed by the roots all the way up to pH of 8.5