Most of that applies to soil which is totally different than coco. My first week feeding is always 1.0 ec and second week is 1.3-1.4 ec,plants are happy about it because they are in coco and looking for feeding to gain energy. autos or photos doesnt matter.Your seedling doesnt have signs of overfeeding,dont judge by ec yet. Ec is not something to follow strictly,ph is much more important. This seedling is looking good for only 4 days,keep doing what you are doing mate.it is still establishing roots,dont expect anuthing magical for first week.week 2 will be where it'll explode. in case of burn,you can safely back off nutes a bit and recovery is within a couple of days at most.coco is faster than soil,no need to be scared.sudden problems,quick recovery.i see you feeding schedule,you cant overfeed with those dosages.just wait for your seedling to settle roots in coco which takes about 10 days.patience