I like to keep it simple, I mix coco with peat and ewc, this should be a nice mix for vegging any plant at good conditions on only RO water or even dirty tap (works fine with even 0.9 ec from tap) after they bushed up I start feeding according to my water starting point, let's say I use RO, so when I start feeding I give 0.3 ec the first time, 0.5 the 2nd and so on, I move up or down according to the plants not the charts, and also move slowly in order to give the roots time to get used to the new solution.
Roots love consistency, so I maintain in each watering the same or a lil up or down feed.
Flushing will shock the roots, overfeeding will shock the roots and the plant, avg consistency is the key.
Most people refer to nutes as food, no, water is the plant food, focus on how to make it perfect in terms of what you put in it and how much at what time.