The reality is you don’t need to be told when and how much to drink. We have a 300 million year developed system that tells you with exquisite accuracy how much you need to drink and when you need to drink. It’s called thirst. If you rely on thirst you won’t ever become dehydrated, and you won’t also ever become overhydrated.
People try to complicate the body and it’s processes, when it does a hell of a good job on it’s own. We haven’t evolved this far with bodies that don’t know how to regulate.