Dont worry about a pale colour at the beginning. They dont really need much nutrient at the beginning so chances are very low for too less nutrients.
The first 2 weeks are slow because they building up a solid root system.
The growth will be exponential once the roots have developed.
Imo the explotion in size will happen when you have like 5 leafpairs.
Once you have some real canna leafs the colour is an good indicator for nutrientneeds - deep green is good (but not too dark -> too much nutrients).
Dont overwater them, because roots need air to breath, but overwatering with coco is close to impossible. Just hold them moist, because thats what you have to do in coco.
Soil needs to get drier after watering for air to reach the roots, this however does not apply to coco. But if unsure: dry is better than too wet.
For lights:
At the beginning they dont need much light because they dont have leafs to work with it. When you have some developed leafpairs turn them on max.
For example at my grow after like 14 days i turned all 480W on the 6 plants.
When i started i only used 120W, then 240W and finally full 480W.
At the beginning patience is key to success!