Everyone is different. You can start off with 1/4 tsp on your tongue. Monitor how you feel throughout the day. You should learn the signs of low sodium and add 1/4 more when needed.
Low Sodium Symptoms
https://www.perfectketo.com/keto-electrolytes/
Symptoms of electrolyte deficiency include:
Heart palpitations or racing heart
Feeling shaky, dizzy or weak like you’re going to pass out
Headaches or migraines
Leg or other muscles cramps, such as getting Charlie horses at night
Trouble with constipation and bloating
#1: Sodium
Use more salt! Sodium gets a bad rap for causing health problems, but things are a little different on the ketogenic diet. When excess water is dumped from the kidneys, electrolytes like sodium go with it [*].
Sodium is an important mineral and electrolyte that helps retain water in the body and keeps a proper balance of other electrolytes. Sodium is also very important for muscle and nerve function.
You can replenish sodium by adding salt to your water and food or by regularly drinking bone broth (Kettle and Fire is a good brand if you don’t want to make your own).
*Good luck. I 'm glad to have read this; It is a mistake I make often even when not fasting.