Depending on which brand of nutrients you are using you can find feeding tables that will give you target EC or PPM levels to try and get for any specific week of growth. the nutrients NPK are mobile nutrients they are needed in every stage some more than others but they are ALL required.
If you wanna find the feeding table for your brand of nutrients just simply google "your brand feeding table" and you will find it :) 👊 On a more personal note I can see you are running the famous Larry Lemon OG I have these seeds may I ask which plant is mr Larry ? you have good experience with seeds man ?