Autos prefer to be in their final pot to start. Measure your EC and pH daily, especially if coco is your main medium. For pH, 5.8 is perfect in coco through veg then 6.0-6.2 for flower. Follow EC recommendations online,, much moreso than the instructions on the manufacturers bottle. Remember that coco often holds onto residual calmag so it's a good idea to alternate between using it and not using it.
Look up a ppfd map for your specific light. You want 400 for seedling, 600 for veg, and 900 for flower. You can go higher if you have CO2.