watering is reactive... you react to the outcome.
you are soilless so it's even simpler.
fertilize every single irrigation around 1.3-1.5 EC. ratio/balance is obviously key, so you'll have to work that out over time.. observe and adjust.
in coco, wait for top layer to start changing colors, and it's a good time to fertilize again. If the plant drinks fast, more frequent fertigation is possible and you do realize additional growth from that method. I'd suggest forming a good baseline doing it a safe and conservative way first, then you can more easily assess whether any risks of doing it are worth it or not.
you need at least 33% loss of water weight before you fertigate again or you'll just drown the roots or increase risk of infecion in roots. i wouldn't do this early on in life. a larger more mature plant or as you go into bloom, sure. I'd rather i grow my roots early on in a way that makes them grow deep and aplenty. roots follow moisture in a reactive way. you get fewer superficial roots (at surface they become useless if exposed to light) by having a good wet-dry cycle. the top will always dry first.
if you want to do multiple fertigations a day or water when the pot is only lost 33% of the water you previously gave (can feel the weight to judge), wait until the plant is a bit more mature or flip to bloom.
growth is a curve. it's slow at first. these sort of things help, but not nearly as much later one. it's worth the small loss for improved root growth early.
