You aren't going to be able to say the X drops of ph up or down will change the solution X amount. it's not algebra blink.....they are living plants and each one is a bit different. Think of it has having a couple children...they're ALL going to be different from each other and act a bit differently accordingly.
You may be able to feed both kids the exact same thing (and I mean EXACT) but they will respond differently. So do plants.

The only real way to do it is with a dropper, your ph adjuster, and a good, accurate meter. The amount of nutes in your system will also affect ph, as will the amount of 02 in your water (raises ph) so you just don't get to preplan some stuff like how much ph up or down you will need.

Hydro should IDEALLY be checked twice a day but can get by on once a day if the system is stable.

One last thing....almost ALL hydro nutes LOWER ph.....if you added some grow your ph is most likely LOWER now than it was so check ph OFTEN.