Some things I learned/read/experienced about coco this grow. Drain to waste.
1 Feed everyday to runoff, 20% I measured it to make sure at first.
2 feed all nutes at once. Don't cal/mag one day and whatever the next. Everything has to be there in close to right quantities for anything to be used.
3 you can over water coco, if the plant isn't rooted out well. If it's droopy let it dry out a bit
4 I check my runoff once in a while. It should be close to what I'm putting in. Maybe higher ph and ec, but still within a safe range.
5 environment is just as important as lights, nutrients just need to be in range the plant handles the rest. Getting temps and humidity to stay where you need.....
I would water less ( once a day ) and feed less ppm if it were me. Like 600ppm max or 1.2ec and as close to 5.8 ph as you can get.