I am doing well on up to 500ml per day. If I go up to 750ml it’s too much for me. Increase the amount slowly and then stay at the amount you are comfortable with.
Commercial and home made are way different. Home made can cause die-off easily. It did for me. Initially you might have some gas and bloating until your body gets used to the new probiotic but after about a week or so it should be fine.