https://manicbotanix.com/hydroponic-nutrient-science/
Taking the above article and applying some nutrient science as well as a troubleshooting guide I ran across:
https://percysgrowroom.com/ec-and-ph-fluctuations-in-hydroponics/
Because of this, the numbers for weekly feedings are baselines only. Micro-adjustments are made as frequently as needed to keep plants happy by shooting for a naturally fluctuating pH between 5.8 & 6.1 and a close to static EC